There should be no issues using MC on windows 7.
Up until about 6 weeks ago Windows 7 was installed on one of my drives and not only did it run MC without issue, I also used it for a short time as the sole development platform. If windows 7 was a little more robust I would probably still be using it, despite high end hardware (i7 920 with 12GB DDR3) I found the OS to be a little unstable, not much, but my main PC is often running for weeks at a time, and even an occasional crash is not acceptable.
For the time being I am back to switching between Vista Ultimate 64 and XP (32), both of these setups are rock solid, although I dare say that I will end up using W7, I may try it again after RC1.
MC's build settings are x86 (32 bit) and .net 3.5 and should work correctly on all windows platforms that support .net 3.5 (32 or 64 bit).
I have read the MONO supports vb.net (2.0), I may start releasing a (2.0 framework) version, or even switch to it completely (
http://www.mono-project.com/Visual_Basic), in which case MC will also run on Linux OS's.