It hasn’t shown up on Exchange yet, but it is already available for download on the Sourceforge page. There is an update to IFC 2015 (the one that is really robust, fast and accurate for Import and Export), and also some updates to 2014 IFC addins.

Direct link to the MSI installer for Revit 2015

Some of my testing:
30% file size reduction in RVT when using Link IFC on 85mb steel model from Tekla v16.1
v15.1.0 = 297mb
v15.2.0 = 210mb

66% file size increase in IFC when using export IFC to all proxies:
v15.1.0 = 288mb
v15.2.0 = 478mb

ifc2x3certificationlogo_arch-e-25-9660159

Some key Export improvements from the readme (I’ve underlined points of interest):
The functionality for creating and using user-defined property sets has been greatly enhanced. This includes:
– Added a “DefaultUserDefinedParameterSets.txt” file to allow a user to create user-defined property sets for any setup, including the in-session setup.
– Added the “IFC2x3 Extended FM Handover View.txt” user-defined property sets file to the installation. This also fixes a typo in the original version.
– Allow the user to specify any file as a user-defined property set file, instead of being forced to use the default name and location.
– Increased the types of fields that can be used from the original 4. The full list is detailed in the DefaultUserDefinedParameterSets.txt file.
– The Setup dialog for the export alternate UI has been split into 3 tabbed pages to make it easier to find and understand the export options.

– Significantly improve performance when trying to export a highly-tessellated geometry.

New Import Functionality:

– Add an “IfcMaterial” field that contains the material name(s) associated with the element.
– Add an “IfcSpatialContainer” field that contains the name of the project, building, building story or space that contains the element.
– Create multiple layers for simple cases of elements where IfcMateralLayerSetUsage is defined.
Import IfcGrids. There are some fundamental differences between IFC and Revit Grids, most notably that IFC grids are per-view, and Revit Grids are per-model. As such, there may be cases where some grid lines show up in more views than initially designated in the IFC file.
– Improve healing and logging of imported solid data that is slightly dirty. This should result in fewer missing objects.

Import Bug Fixes:
Fix “missing” faces when elements were cut by openings and the IfcOpeningElement sub-category had its visibility turned off.
– Handle unbound circles used for profile definitions in certain cases.

Heads-up https://twitter.com/digiacomoemma/status/517072219739291648