String Format Diagnostic (v184.108.40.206)
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 (v220.127.116.11)
String Format Diagnostic (v18.104.22.168)
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.