I think one thing a lot of people are tripping up on is what is being worked on, and how .NET fits in.
Ximian's Mono project is really only the VM, runtime and compiler technology, plus a few other things.
the dotGNU project (www.dotgnu.org) is more a replacement for all the parts of the .NET infrastructure, including passport and other web services. It is a larger attempt than just the Mono project alone, and I'm PRETTY sure there is little or no overlap in their efforts, or so i hope.
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