I went from a Panasonic Lumix TZ30 to this Nikon. You do not have to learn it all in a day. I've read elsewhere not to make such a big jump, but that is a load of crap. The journey, not the destination is the most fun. One tip, don't change all your settings to those that Ken Rockwell recommends and in general you don't have to muck around to much with settings to start. Ultimately the same basic rules apply, ISO, Aperture and Shutter Speed. Beyond that, shoot, shoot, shoot. I take at least a thousand images a week. All the decent software including NEX2 will show you the Metadata for you to compare your shots.
My only recommendation is to shoot in Aperture Priority most of the time(at least to start). The other thing I spend a lot of time changing is minimum shutter speed in the menu as I like to shoot BIF. I also only ever use back button focus.
You've bought one of the great bang for your buck camera bodies. Enjoy! You can view my album here under dramtastic and if for any reason you like what you see, I'm a novice, I will be happy to send you any changes I have made to my camera menu.