The sony slr range is quite good, in both the image and video quality... the boys are right in saying a lense makes all the difference... i work at a camera house store and i can definately vouch for canon as their quality of lense and general build is top notch... agreed with soksta, if you go a canon and take it to motor sport events, a 55-250mm IS lense with a teleconverter would do very nicely..

have a look at the canon 550D its well worth the money, its quicker then the a55 (3.7 fps from memory), 18MP and also does full HD video... between the canon and sony alpha lenses, the canons feel much more solid and smoooth... carl ziess lenses are a better feel then the alpha series...

all in all the a55 is a great camera but with a canon you have a larger range of lenses and their quality is top notch...