I have an e71, AT&T 3.5G and I am in no mood to switch carriers.

Will the n900 offer all the functionality that the n810 offers right now? Can I use it as an "internet tablet" rather than a cell phone? Can I connect the n900 to my e71 and be able to browse at 3.5G speeds on it?

(also, I am guessing the Assisted-GPS is not going to work since the n900 won't be receiving any cellular connection. But I can nevertheless still connect to the GPS satellites right, albeit taking a while to do so?)

Additionally, anything that the n810 can do but the n900 can't (or needs a SIM card to do?)