Going back to the original post in this thread...
why I think that Canon 60D won't be such a great upgrade over the Canon 50D DSLR.
Looking back, the 'next' camera in this line has rarely been a great upgrade over the former model. I'd grant that the 20D was a good deal better than the 10D, but the 30D was only a face-lift and not worth upgrading from the 20D. The 40D was a decent upgrade over the 30D, but mostly because the 30D was really just a 20D, and thus several years old by then. Most internet gum flappers were disappointed with the 40D because (like always) they expected a lot more and for less money. The 50D wasn't much of an upgrade over the 40D...which seams to fit the pattern.
HOWEVER....you need to consider that the 'target market' for the new model, isn't really owners of the previous model....it's owners of past models or lower (Rebel) models. For example, the 50D would be a tremendous upgrade from someone who owns a 20D or 30D.
So to extrapolate this...the 60D (if that's what is coming) would probably be a nice upgrade for people with a 20D, 30D or maybe even 40D....but maybe not worth the cost for someone who already has a 50D.
And because the internet reviewers will all be comparing the new model to the previous one, they will be disappointed that's it's not a 1Ds at the price of a Rebel. (and that's something I can predict with a lot more certainty than trying to guess what Canon will do next).
I'm very interested to see what Canon comes up with next. I'm due for an upgrade from my 20Ds. Do I want the new 60D, if it comes out?...or do I look at a 7D? or do I take the nice step up to full frame? (and have to buy new lenses). Heck, I'd be happy if they just gave us a 50D at a lower price.