The plastic body which makes the 60D lighter is not really a bad thing on my list either.
+1 - when I bought the 60d I was very weary of the plastic body and even considered buying one of the last 50d - today I know that it doesn't make much of a difference, if I drop the camera the first thing to break is the lens or parts of the camera that aren't protected by a metal body either (displays, flash, ...).
Looking good to be returning to build of 40d/50d hope it is in same body as the 7d and would come with Wi-fi and GPS like the great 6D.
I'm pretty sure it'll be the same body size as the 60d - Canon obviously thinks this size and layout has a future or they wouldn't have put the 6d in it. Imho the only questions are:
... will the 70d have gps/wifi and not an internal flash (that's where the antennas are on the 6d)? Or can they do both, probably in a full plastic body again for the gps/wifi signal?
... will Canon just do a 650d-style sensor update for live view af with maybe some iso optimizations like on the 6d - or will they really put a new sensor gen in it? My bet is that only the 7d2 in the end of 2013 will get a really new sensor, Canon has enough other firmware and hardware improvements in store to make the 70d a noticeable update from the 60d.