Sony a33 vs Nikon d3100?

My budget is 800$ I will be shooting outdoors, in low light conditions, and video. If you have experience with either of these cameras please give me your opinion. Don't just post something you found off of a website, i can find all that myself.

Nikon D5100 16.2MP CMOS Digital SLR Camera with 18-55mm f/3.5-5.6 AF-S DX VR Nikkor Zoom Lens
Nikon
$899.00

Best camera.

Tough one.
As a Sony user I would tell you the a33 in a blink of an eye.
However i wouldnt trust the EVF if you focus manually with a wide aperture lens for example.
the screen is superbe though and has a super fast 7fps continuous shooting mode.
on the other hand i hate the handling of the d3100 with a passion (see my answers for more details), really it will be a matter of handling the cam and decide upon the one that feels the best.
you will get great result with both and there are plenty of lenses available for Alphas so no reason to be scared of putting your money on the alpha system. You can find lenses from tamron tokina sigma zeiss minolta etc…
hope this helps