To add to this, Eric Lippert, a principal dev on the C# compiler team, mentions this in a StackOverflow response (http://stackoverflow.com/a/8899347/59111). He also blogged about the issue in general in a two part series, the first of which can be read here: Closing over the loop variable considered harmful (http://blogs.msdn.com/b/ericlippert/archive/2009/11/12/closi...).