Links for Revit 2015 UR9 for R2:
Download link
Enhancements List

Download link for Revit 2015 UR9 not for R2:
Download link

Enhancements List (plain text):
Improvements made in Update Release 9
 Revit 2015 build: 20150702_1515
 Revit 2015 R2 build: 20150704_0715

Autodesk® Revit® Platform 2015 Updates
 Improves stability when deleting an element which contained an invalid partition ID.*
 Improves visual fidelity when exporting to DWF.*
 Improves data consistency between a schedule view and a schedule instance on a sheet.*
 Improves stability while upgrading Revit 2012 projects.*
 Improves stability while editing families.*
 Improves stability when using the Options dialog to log into A360 from a workshared central file.*

Autodesk® Revit® MEP 2015 Updates
 Improves stability when upgrading a project that contains user-created pipe types.*

Autodesk® Revit® Structure 2015 Updates
 Improves stability while when placing a slanted column or a beam based on a Generic Model Line based family.*
 Improves stability when reloading an annotation symbol family used as a symbolic representation of brace elements on plan views.*

Autodesk® Revit® API 2015 Updates
 Improves stability while when editing families which use external resources for keynotes.*

Straight copy from Revit Clinic:

Update Release 3 for Revit 2015 has been released to the App Manager. However, if the App Manager is not finding the update, you can download them directly from the links below:
Revit 2015
Revit Architecture 2015
Revit MEP 2015
Revit Structure 2015
Revit LT 2015 (64-bit)
Revit LT 2015 (32-bit)

Original post:
Revit 2015 – Update Release 3 – The Revit Clinic

My top 4 new features / changes in Revit 2015:

  1. Sketchy Lines!
  2. IFC Link
  3. Revision cloud arc length (ie. “Revision Improvements”)
  4. “Username has been updated to match Autodesk 360”

Official page for Revit 2015 new features:
New Architectural Design Features | Revit Family | Autodesk

If you want to talk about Revit 2015, your expectations and the new features in general, check out this thread:
Today is the day!

Steve’s post:
Revit OpEd: New Feature List for Revit 2015

Sean’s posts:
What’s new in Revit 2015 | Paradigm Shift
and system requirements, including running Revit 2015 on a Mac

Chris’s post (some valuable commentary here):
Revit Rants: Revit 2015

John Flanagan’s post about Sketchy Lines:
Revit Architecture 2015 – New Features – Blog – CADline Community

Oliver describes the new exp and ln functions before they are even listed in Help:
at this link

 Steve also discusses them here.

Lejla’s top 5

Structural enhancements like Justification Points, more info at:
Revit 2015 – Structural Framing Enhancements | Autodesk Revit Structure

Structural reinforcement for Parts:
Ideate Solutions: Autodesk Revit Structure 2015: Reinforcement for Parts

To learn more about Sketchy Lines, check out:
RevitCat: New Sketchy Lines in Revit 2015
(Tim recommends setting both sliders at 3 and starting from there)

David Light also posted about Sketchy Lines at:
Revit : Revit 2015 – sketchy lines

More on the schedule changes:
RevitCat: New in Revit 2015 – Schedules & Parameters

Dan Stine’s post (It includes some detail information on the Hidden Lines changes in Revit 2015):

Revit Structure 2015 showing Rebar improvements, by Lawrence:
Revit Structure 2015 – New Reinforcement Tools | Autodesk Revit Structure

To find out about performance enhancements in Revit 2015:
Revit : Faster….Faster…..Revit 2015

Perfect Project (Russian blog) has a very detailed post, mentions the Image Type parameter for families.

Russian forum post, with details and lots of screenshots. eg number of filters increased to 8 in schedules, labels in 3D views react to changes more predictably.

In Russian,Русский/Новые-возможности-Revit-2015/m-p/4925120
Translated version

Suite changes and updates:
Autodesk Unveils 2015 Suites for Building and Civil Infrastructure Industries
including a few downloads like

Download Building Design Suite 2015 backgrounder
Download Building Design Suite 2015 backgrounder
Download Building Design Suite 2015 backgrounder
Download Building Design Suite 2015 backgrounder

Redstack page:
New Autodesk 2015 Design Suites

Another nice summary:
Top Reasons to Choose Autodesk Revit Architecture 2015 | CADD Microsystems 

Lot’s of new features pages for different Autodesk 2015 products at:
Cadline Insider Blog – Cadline Community

AutoCAD 2015:
AutoCAD 2015 in two minutes | CAD Panacea

Inventor 2015:
Autodesk Inventor 2015 Released – Whats New? T-Splines? | Design & Motion

Here is what the new Revision Cloud tools look like:
Today is the day! – Page 4
Ben also re/posted a few videos demonstrating Revit 2015 features.  I have started a video playlist of these, and also added a summary of Revit LT 2015.  I will add to this playlist as further videos become available.  It is embedded here:

Some good informational videos from the Revit 2015 help site
New In Revit 2015
New Feature Videos 2015
via The PPI Group Blog: New Feature Videos – Revit 2015

What’s New in Revit 2015 and Related Autodesk Products from Alfred Huang on Vimeo.

Autodesk® Application Manager is a cloud-centric software delivery solution that includes a desktop client component that is packaged and installs with all Microsoft Windows®-based Autodesk 2015 products or suites. The solution replaces previous product update components, specifically LiveUpdate, portions of InfoCenter/Communications Center, and CAD Manager Control Utility (note that these will remain in production to support previous version products). 
Thank you for your interest in Autodesk® Application Manager, a new software delivery solution that makes it easier to discover and obtain updates for the 2015 products you own and manage.

For more information about Application Manager, please visit About Application Manager. This document describes what’s new in Autodesk Application Manager for 2015. It is recommended that you read this document to become familiar with the features in version 2.2, the first version generally available to customers (previous versions were only available to Beta participants). 

What’s New in Application Manager 2.2

Version 2.2 includes a number of quality-focused enhancements, which are delivered to the desktop client as a self-update to previous versions (such as 2.1 shipped in product media), or as a new component fetched during 2015 product installation. In addition, several improvements to the Autodesk cloud delivery platform power a user experience that is highly secure, and scales to support heavy delivery request volumes.

Significant Features Delivered in Previous Versions

  • Improved Self-Update Experience – increased flexibility when new self-updates are released for Application Manager. Most Application Manager–specific updates are now backwards-compatible, and do not force users to self-update to continue using the application. In rare cases, such as when underlying API changes affect compatibility, a self-update may be forced.
  • Local Settings – allows users and administrators to control how Application Manager behaves, by specifying local settings or preferences such as network proxy, alerts, default file location, and update check frequency. Also supports import/export of settings file for use on other desktops.
  • Enhanced UI – added features for multi-update handling, sort, filter, and link to long description (making it easier to understand update’s value and function, what it fixes or enhances).
  • Customization in Deployment – a new feature in the deployment wizard allows CAD/IT/BIM administrators to specify custom settings for managed users during deployment creation. If the Application Manager Client is not desired, it can be prevented from installing in this feature.
  • Fixes to Critical Defects – as part of the Beta test and related quality assurance efforts, a number of priority defects have been fixed in each release.

Read more about it:

Download it: