I also played with the 60D at canon vivo a few days back.
I am a casual DSLR user with a 500D so dont take my opinions too seriously as they come from a very amateur point of view
Things that stood out for me:
1) The ergonomics were excellent. Much better than my 500D (of course). I have very large hands. I was surprised how good the grip felt in my hand
2) It was very lightweight. I sensed no loss of quality from the plastic outer shell.
3) I do not like the mode selector knob and delete button being on the top left. As a 500D user i am very used to being able to do EVERYTHING from changing modes, to reviewing, cycling through, then deleting pictures, all settings etc etc with just my right hand, while holding he camera. My left hand is always free. I seriously cant understand why this cant be done with the higher end bodies which force you to use both hands once you want to do certain things. But i do like the button layout on the 60D more than that of the 7D or 5Dm2 because more buttons are pushed to the right (due to lack of space on the left as a result of the flip-out screen)
4) The lcd picture quality is freaking amazing compared to my 500D and the pictures look great too. The flip out feature is not a big deal to me but i can definitely understand the appeal
5) Love the larger viewfinder compared to the 500D....but once i look through the 7D's and 5D's VF, nothing else comes close...lol
6) I like that it uses SD cards as opposed to CF
7) I seriously wish it had more AF points. 9 points seems very rebel-ish, although its great they are cross points
Overall i love the ergonomics, LCD + pic quality, and the fact that it uses SD cards, and well the top LCD. Which all makes sense since canon targeted their 60D to 500D users like myself. But would i buy it? Hard to say,but probably not. For me to throw the money down...i want the best and biggest viewfinder i can get: as close to 100% coverage and 1:1 magnification as humanly possible(to me this makes a massive difference). Which means for now, my next upgrade is still either the 7D (or 5Dm3 if it ever comes out, probably not the 5Dm2 though unless i get a really good deal because the LCD is starting to look a little outdated compared to the 7D/60D)