Having owned both Sony and Nikon cameras I understand there are benefits of both
Nikon - can get hold of rental lenses, if you plan to throw lots of money into photography, the top of the range Nikon kit is fantastic.
Sony - in camera VR, lots of old minolta lenses available.
I would say that if you are a keen amateur on a budget I would go for the Sony. Together with somthing like a Sigma 24-70 2.8 and a Minolta 70-210 F4 (beercan) you can have a decent focal range, image stabilised and sharp, relatively fast lenses for a resonable price. That is just not an option with Nikon or Canon.