Nikon will soon begin shipping the anticipated D600 full-frame DSLR. With 24 megapixels, it has more than enough resolution for anyone, and costs $900 less than the popular D800.
We'll have to wait and see just how well this sensor performs, but my guess is that it will be very highly rated, and will outperform every Canon camera with regard to image quality.
If you must have a full-frame camera, the D600 will be an excellent choice, providing great quality for a reasonable price. If you are on a tight budget, the D3200 will get you similar image quality for 1/3rd the price (and it even comes with a lens). Yes, the D600 will have better high-ISO performance, but most people don't use high-ISO for anything serious.