720p works fine for us. We're using IndigoVision 11000 cameras primarily because their picture quality is acceptable (after they made modifications to their IR filter) and because the cost of third party cameras plus IV's license leveled the playing field.
If IV's cameras didn't fill the bill, the best picture quality on table games we saw was in the Axis P33xx-series. One caveat: Axis was unable to provide dual 30fps streams so if you desire two streams like we do (one TCP/IP stream for recording and one Multicast stream for "Live" viewing), you might want to look elsewhere. Our limited testing of Bosch Starlight cameras indicated good results.
Our initial testing was "limited" to just finding cameras for table games due to our determination that our analog overhead cameras were basically useless once they are fed into encoders. Encoder resolution made it so we once again were only able to identify the suits of ~40% of cards after getting that figure up to nearly 100% on the best analog cameras.
Axis M-series, Ganz and a couple of others displayed distinctly inferior pictures in good part, I suspect, due to lighting issues - something most casinos I've known have problems with.
We will revisit fixed cameras again in the future.
I was looking at the VIVOTEK MD8562 2MP for desktop use. The camera has a 3 axis lens adjustment and can sit on a tabletop with no exposed cable.