Visual Studio as a development it doesn't matter at all. The matter is .NET Framework version. VS 2012 supports .NET Framework 4.5 which looks like not supported by SolidWorks yet. The latest officially supported Framework is 4.0. Check this article:
You should use different Interops to work with 4.0 and 3.5 and earlier.
Artem Taturevych, Application Engineer at Intercad (Australia)
translationXpert – add-in to translate SolidWorks models
myIntercad – an integrated tool for SolidWorks Professionals
My main concern is the addin project template that available present for 2010 and earlier versions.