1) There is absolutely no reason to get the 3G version. I did just in case something interesting was implemented at a certain point but it doesn't look like it ever will. To summarize, you'd need a data plan with AT&T and no games ever at all let you play multi over 3G. It's basically for apps and Near, so you decide on that one.
2) Yes, the Vita had one of the best software launches of all time and there are a lot of great games to play on it. Some examples include Hot Shots Golf, Uncharted, Technicka Tune, Virtue's Last Reward, EDF, Persona 4 Golden, Soul Sacrifice, etc.
3) No, the second you hold this beautiful hardware in your hands any doubts you might have felt will be burned away, replaced by a hatred for the people who are passing the system up and are instead making the ridiculously inferior 3DS more popular.

