I wish I had bought the C2 instead.Dave,
I feel exactly the same way. My plans are in the very near future to move my C3 to the rear center so I have an excuse to get a C2 for up front. It's just a thought.
Also, in response to Craig O:
I think you summed up the differences between the 7'a and 9's exactly. The main advantage to the 7's is if you intend to listen to music in 2 channel without a sub (something my Yamaha doesn't seem to want to do without changing it's setup?) or if you want the mains to handle or at least help with LFE. In all cases though, this means you're looking at needing a beefier receiver to take advantage of the 7's over the 9's too.