Canon T1i / 500D vs Nikon D5000 vs Nikon D300 – Ken Rockwell:
If you demand more pixels and count every one, the Nikon D5000 (or equivalent D90 or D300) gives superior technical results from their lack of noise-reduction induced smudging, ability to correct lens defect color fringes and more reliable AF system. If you look at your photos at 100% on-screen, the Rebel T1i images look more like they came from a compact than an SLR.