Blender version 2.72 in the .zip downloaded from blender.org there is a new file called blender-app.exe in addition to blender.exe. What is blender-app.exe for? Which file should I use to open blender?
As @Lord Spectre said,
blender.exe is a launcher to
From this thread on BlenderArtist:
When the devs moved Blender windows compilation to use mscv2013, it broke the OpenMP support for windows (that makes some functions multithreaded) (while legacy mscv2008 builds were still working good with OpenMP)
This nasty problem was noticed first in a sculpt mode report in which a simple brush stroke on even very low poly stuff was pulling CPU usage to 100% (without any actual performance gain) instead of the +/- 30 CPU use.
As a solution, the devs went with a "launcher" that would apparently set some variable to lower the impact of OpenMP breakage , the discussion between dev can be read on the august mailing list "[Bf-committers] OpenMP issues with msvc2013 builds".
blender.exe is about 500Kb in size while blender-app.exe is 76MB, so I think that now the main executable is blender-app.exe, and blender.exe is a launcher made for backwards compatibility. In my opinion, you can use both indifferently. I'm using blender.exe and it works as before.