String Format Diagnostic (v126.96.36.199)
With this release I've managed to back-port a verson to VS2013 (Roslyn CTP) as well as a version for VS2014.
Download available on the projects CodePlex page: String.Format Diagnostic (v188.8.131.52)
String Format Diagnostic (v184.108.40.206)
I've been spending some time developing a Roslyn Code Diagnostic to analyse and validate formatting strings in both VB and C#.
Proud to say that succeeding in creating a proof of concept a few months back (link to blog post
Over the intervening spare time I have been slowly improving it.