VS2012 RC would nest related javascript files in the solution explorer in the same manner as default.aspx and default.aspx.cs. For example, the minified version of a javascript file would appear nested under the debug version: jquery-1.7.2.js would be the parent to jquery-1.7.2.min.js.
When I upgraded to VS2012 RTM, this stopped working. The "nest related files" button toggles the behaviour of .aspx and .aspx.cs files, but .js files remain side by side.
What happened? This was a really nice feature.