LOL! I know I know...sort of a long story. I'll try and summarize so you won't think so little of me.
So my friend has been shooting pro for a while now. He had started out with a Nikon D50 just as a hobby and decided he liked it enough to start attempting to make some money (not full time yet but working on it). He hooked up with someone who mentored him and he happened to be a Canon person. My friend (obviously) ran into the limitations of the D50 and, when he upgraded he made the switch to Canon. I bought his old D50 and started out like him...hobby shooting.
Well, fast forward to today and I'm getting requests to shoot sports since I'm always shooting at my son's wrestling matches (and I'm one of the coaches). I am looking at starting to do some sports photography on the side (another long story I won't bore you with here). Unfortunately, I ran into the low-light limitations of the D50 (and I LOVE the D50, btw). I borrowed a D90 from a friend--and loved it. My mentor kept teasing me about buying his 50D so he can get a 7D. I need to upgrade so I started thinking...
-Need something with better high-ISO qualities than the D50--Nikon (apparently) does the best at higher ISOs but I've found the 50D to be more than good enough.
-I understand the 50D has a very fast focus system--not as fast as the 7D but fast and built more for sports photography.
-I don't have a lot invested in Nikon gear yet so, if I was going to switch I could do it safely now.
-My mentor and another friend who shoots pro both shoot Canon. Easier to get help when we're shooting the same gear. They also plan to use me as a 2nd shooter for weddings, etc. I figure shooting with the same gear might make more sense there, too.
-Getting a great deal on the 50D from my friend.
Basically, I love Nikon and never had anything against Canon. Clear as mud, right?