Can't really say much about the 2011 model, haven't got one yet. 7500 seems high. the 09 and 10 are very similar, the 10 had a different map and fuel settings making it feel stronger, not sure it is. in fact I think the 07 was the animal for 450's.
Upgrade, start a savings account, cause when it goes hold on to your wallet. no just kidding. I currently have 3 450's and have not had a problem with any of them. 2 are full on race bikes that see new cranks and valves every year the 3rd is pretty much stock and is raced as well but in a different environment and it hasn't had any issue either, but it is going to leave as soon as my dealer gets an 11.
Four strokes are great bikes but be aware that they are full on race bikes and as long as you change oil and keep clean airfilters they will run for a long time. you start running into trouble when you try to jack the HP up, they are at the edge of reliability right now so when you ask for more be prepared to have issues or do like me and get rid of the issues before they become issues.
seriously for upgrades, I would ride out the stock piston and ditch it for a forged wiesco, I would look at the 22mm triple clamps or did the 11 come stock with the 22mm? set up the suspension, yeah that would be my first investment, of course a pipe, and then its a bling thing.
edit: so i read your post again, that was 7500 for a 2010 I definately wouldn't go there, I was thinking for a 11
