I know it's called a 550D outside of the US, but you should have titled it T2i so everyone from the states knows what you're talking about.
Mark II? You mean a 5D Mark II, 1D Mark II, or 1Ds Mark II?
If you've never used a Mac, it takes a while to get used to it. I love the Mac keyboards and laptop keyboards, they are much easier to use then most PC laptops that try to fit too many keys in such a small space.