<div id="linkdxomark">This a comment for <a href="
http://www.dxomark.com/index.php/Cameras/Camera-Sensor-Database/Canon/EOS-650D">this page on the website</a></div>Sensors are now pretty damn good,have been for a long time and unless you are shooting in outrageously bad conditions they will out perform you.
I suggest that better lenses are now far more of an issue as even the best of lenses have faults and the modestly priced lenses are almost unusable on the cameras with better sensors.
Lenses are definately the top issue at this moment, Canon being quite strong at that end; but you can't simply ignore the Sensor performance. Outcome on Canon 650D is really bad. I mean things are not very clear on DXOMark website but if you look at dpreview on all ISO settings, you will see Nikon D5100 is beating Canon D650 with huge margins. Even ISO 800 is quite noisy for my liking.
Having said that, I was not really expacting much from 650D, I had this kind of impression Canon won't make any progress on APSC sensors on quality (improvements are on the other grounds) and DXOMark score will be disappointing (fairly) as they are more focused on FF. They are projecting 650D to people who just want a smaller and lighter body to go with their existing professional gear, or someone at beginer's level, who don't go to review websites.
http://www.dpreview.com/reviews/canon-eos-650d-rebel-t4i/26