The Logitech C920 is awesome. Great video quality. Nice camera mount. Good utility software to adjust white balance, exposure, etc. (PC only).
Andrew posted a news release recently about the C930e due out next month. I'd hold off and see what that one looks like before I went for a C920 today.
You can see the C920 quality in my show today (below). And that's only using 864x480 resolution (standard resolution). The C920 will do 720p and 1080p as well.
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