Spent another 15 minutes playing with a J1 at Best Buy tonight. Took a few photos of myself and was impressed with the sharpness and detail it rendered as viewed through the LCD. ISO 1600 (well exposed at 1/160) was actually nice. I'd say it's on par with a 12 mp m4/3 sensor. Maybe even a bit better. I like the styling of the J1 better than the V1, which does indeed look like a Tetris block! Unfortunately, there are no V1's at the retail Best Buy stores.
I can't believe I'm actually liking a Nikon ... strange feeling.
With all due respect, it's hard to make an evaluation and a comparison based on seeing the pictures on the screens of two different cameras. Most certainly not sharpness.