If you want to get serious with photography i would suggest a Canon or Nikon. They have the largest selection of lenses. Plus, if you upgrade your camera in the future, the lenses you buy can most likely be used with new camera as well.
I have a Canon T1i, and am very satisfied with it. It takes very high quality photos. Also, might be personal preference, but I have always liked Canon's ability to power up very fast. Almost instantly after you turn camera ON, you can take pictures.
But honestly,s electing a camera is very much a personal preference. Go to a store, try holding some cameras in your hand and see how it feels. You will be surprised by how much difference "the feel" of an camera can make when you are deciding which to buy.
Most important!!!! Do not rush it, make sure you research your top 3 choices.