Sony A57 is much better camera than Nikon D5100.I tested both and with the D5100 is the camera handling totally horrible. On this page you will usually find any image quality(IQ) results quantified by some number, but this really doesn't correspond to the reality.But the IQ is probably the only theoretical positive point for Nikon D5100. Anything else was very disappointing with this camera and I returned it back to store.
Using Sony camera you will find out, that other DSLR manufacturers take their cameras seriously (not as Nikon does) and provide much more added value to the end user.
The innovations provided by Sony during last years are significant and if they'll go this way, you'll be happy to using this system even much more in the future.
