2 completely different style of cameras. d7000 is dslr, with excellent AFF on 1080 video and a good sensor for photos, gf3 is an EVIL camera, small and handy, but it is not out yet, it's not even announced yet.
Just say i am using D7000 and love it heaps, but since you are with D90, i believe upgrade to FX is a wiser step. and you won't be comfortable using EVIL (especially GF3 is much lighter and all the function key will be in the menu) after you get used to DSLR. BTW, D90 wasn't that old, and it is really a good camera.