Dear TS,
Justify your switch of camps by your needs, requirements, and personal fundings. Don't switch camps because many "PROs" are into it. I was a camp-switcher previously, from Sony A200 to Nikon D300 but the switch were mainly due to the likes of ergonomics of Nikon bodies, I, too have a lot of buddies, friends, brothers and sisters using Canon-systems but that doesn't mean I have to follow their suits and persue for Canon systems. Likewise, if you watch as many English Premiere Leagues game, many of the featured "PRO" photographers were using Canon-systems with their Canonic super telephoto lens, so are you going to return to the arms of Canon when you are moving towards sports-photography?
As mentioned in other threads who oftened mentally-challenged between Canon and Nikon by their brands. For goodness sake, brands and camera-bodies are just a tool to pair-up with the users. A truly good and amazing photographs, comprises a good timing, a good opportunity and a good set of skills you possess over your camera-system. Without good skills and abilities to manipulate your camera-system, even a primary school kid using a phone camera can take better than yours.
Truth and facts can be hurtful but don't dwell and overly possessive over camera-systems, hone your skills and fully utilised your 450D's functions and capabilities. Need be, invest on lens... they are the eyes that made your photographs look good.
Look around threads, you will see the wonders of Point-and-Shoot and Prosumer cameras which captured shots that are equally if not far better than some dSLRs.
regards
PS: hope i didnt offend anyone or any brands