I sold all my Nikon and Canon gear a few years ago after deciding the Olympus 4/3 and m4/3 gear was all I needed for personal stuff and work. However, I held onto some of my Nikon flashes and I've picked up a Sigma DP2s and Fujifilm X10 since getting rid of the Nikon and Canon DSLRs and moving to Olympus.
Anyway, I just picked up the D3100 so I could use some of the new Nikon primes that look pretty nice (the new 50mm 1.8G, 85mm 1.8G and 28mm 1.8G all look fantastic). I didn't want a big camera and I liked the deal I found for the D3100 so I decided to go with that DSLR instead of a larger body or the D3200. The D3100 with the new 50mm 1.8G shouldn't be "that much" bigger than my E-P3 with the Pana-Leica 25mm 1.4 with hood (and smaller than the E-P3 with the 12-60mm and 4/3-m4/3 adapter that I often use).
Anyway, I just picked up the D3100 so I could use some of the new Nikon primes that look pretty nice (the new 50mm 1.8G, 85mm 1.8G and 28mm 1.8G all look fantastic). I didn't want a big camera and I liked the deal I found for the D3100 so I decided to go with that DSLR instead of a larger body or the D3200. The D3100 with the new 50mm 1.8G shouldn't be "that much" bigger than my E-P3 with the Pana-Leica 25mm 1.4 with hood (and smaller than the E-P3 with the 12-60mm and 4/3-m4/3 adapter that I often use).