I always, always go with Canon for my cameras. I think I'm going to get the Canon Powershot SD990IS next. I haven't been using the SD series because most of them lacked manual functions, so I have always used the A series-they're good too, but they tend to be bulky because they use double A batteries(not sure what the latest A series models used, but mine uses double A). So anyway, I've always wanted to try out the SD but I didn't like how it did not have the manual control(I like to experiment but I'm not ready for dslr yet), so this one is going to be perfect for me. It's almost like a mini dslr camera. My friends have either a Sony or Casio, which are both really stylish and good, but I've always liked how my pictures turn out better. Plus, I'm a fan of Canon colors!
But it's really up to you and what you're looking for!