I had a 40D and now have a 7D, given that the 60D is based on the 7D I can pass comment also I have used a 60D and know 2 people with the 60D also.
The first thing I will say is the resolution is a real bonus it gives you a lot of room to manouvre when cropping and of course you can blow your photos up that bit more, the video is handy and the built in speed light controller is really handy. The whole camera feels more refined over the 40D and the articulated screen on the 60D works well.
One really nice option on the 60D is you can cap the maximum ISO it will use if you set ISO to automatic which I would of liked on the 7D.
The only negatives I had on the 60D over the 40D is that the build doesn't seem as good and it has some quite gimmicky features, however another feature which I wish the 7D had is the 60D has the ability to star rate images when you review them.
I would go in a camera shop and have a play
