I really hope that the 10.2 release will also support Visual Studio 2013 out of the box.
This week, Microsoft released the final feature update for Visual Studio 2012 and released the 2013 beta.
If supporting the later Visual Studio is too hard to do rapidly then please just provide the ability to install the libraries and not the Visual Studio integration pieces.
We are working on adding support for Visual Studio 2012. More information about this will be made available in the coming months.
The ArcObjects SDK for .NET supports integration with Visual Studio 2012 starting with the 10.2 release. We are also supporting .NET 4.5. .NET 3.5 remains the recommended framework as it is still the prerequisite for the ArcGIS for Desktop or Engine install so it is guaranteed to be installed when you deploy to a machine where Desktop or Engine is installed.
Supporting Visual Studio 2012 starting with version 10.2 is not an acceptable answer. I work on a project for a large Federal client and we are *locked* into using version 10.1 for 3 years. Esri needs to understand real-world situations where people cannot necessarily always upgrade to the latest version of their software. The answer to these kinds of support issues from Esri is almost always "Next version...." - it's just not acceptable.
It's 2014 almost 2015 still the same problem. If you have a platform with 10.1 is should either work with 2012 or AT LEAST let you install the .NET SDK, and not just fail just because you don't have VS 2010 installed. They should have at minimum released a patch to allow the SDK to install without requiring VS 2010. Our use case, for example, is Windows 8.1 but developing an Add In for Arc 10.1 So it's a catch-22. Classic ESRI. I wish a GIS software competitor would come along and force them to listen to customers.