Camera Dilemma

I've been contemplating whether or not I should buy an SLR soon. I'll be graduating soon and that means freedom! I could now go to trips and overnights! Which means more opportunities for beautiful photos! I have my Canon G11 and it's really amazing. I love the pictures and it's very customizable like SLRs but I can't help wanting to have better pictures whenever I go out and that means a semi-professional camera. I don't really know much about cameras but I'm willing to learn, I just don't have the time.

I know people say that to have great photos, we don't need the best camera but let's face it, in a way, we do! So now, I don't know what to get, either a Nikon or a Canon SLR and what model? Of course, I can't afford the most expensive and I'm not in a hurry because I still need to save up for it. I just need some options and suggestions.

Please help me out. Thanks! :)