From Eli's post: "... I wanted to get the whole story. Plus, this was an ideal reason to learn to use the Windows and Xbox 360 CLR profiling tools, which I've put off doing for some time. So, I figured I'd do just that: do a foreach loop over a bunch of collections, use the profilers to see if I'm making garbage, and hopefully we'd all learn something in the process. ...".
It's a nice read, but most important, the results Eli's obtained are quite interesting, so go ahead, pay a visit to "Foreach, Garbage, and the CLR Profiler" and read on.Enjoy!