JayBaz has a great little post regarding the compulsive obsession of many programmers about worrying about micro performance differences instead of writing clean code. Similar sentiments to my thoughts on Generics performance and performance in general.
Keep in mind this is a guy who used to be on the compiler team and REALLY knows the difference in performance of various statements down at the IL level.
(Depending on how soon you read this, you may not be able to get to the post – blogs.msdn.com is down right now. Thank you RSS + Newsgator )