As of right now, there are 2 models. 8GB and 16GB.
However it looks like 32GB will be released by the end of this month and it'll be priced $250 which is the price of current 16 GB model.
So I'm guessing they'd get rid of 8GB model.
Enough jib-jabbering, I like to know who owns Google Nexus 7 and tell me ur experience n etc
* I'm waiting for the 32GB to release so I can cop that