Yep. At the entry level, they are more or less the same. And really, between the canon T1i, T2i and T3i, while there are differences, either one would be a great entry level camera.
I'd suggest sticking with Nikon or Canon as you will start to buy lenses that can be used on body upgrades, but other than that, shop by price and have fun as you wont notice a difference between them
Depends on what your goals are with it. If it is to be a long term investment for you? probably Pentax. They don't strip down their entry level cameras like the rest of the world does.
If you are looking to upgrade down the line into professional gear? go Canon or Nikon.