[masraum]

Whatever memory you think you need, get the next step up. I don't have any music on mine. I got the 32GB. I planned to use mine primarily at home, and I have a cell phone that I can tether for data if I really want/need to, so I got a 32GB Wifi only. If you'll be using yours out-and-about often, and you don't have a tether capable phone, then you may want to get the 3G.

I use mine 99% at the house (so far). I was travelling to my mother's so I took the bluray movies that I own that have the digital copy and imported those into iTunes and put those on my ipad. I then bought a video-out cable for my ipad and was able to play the movies on my ipad on my mother's TV which was really nice. If for any reason you'll want GPS, then you have to get a 3G enabled model.

I suspect that if Apple isn't careful, there will be Android based tablets out that kick Apple's butt, but I don't know that they are out yet. I suspect that before that happens we need the next version of Android (designed more with tablets in mind).

Really, which ipad you get wifi-only or wifi/3G very much depends upon your intended usage.