Went and got the 50D yesterday, and these are my first shots in anger. Yes this is going to be step up in my photography learning curve. But it will be worth it. I left it in Auto ISO mode, and having a play up to ISO 1600 with no huge grain is really nice.
I thought that I had small girly hands, but the heft and weight of the camera, is really nice. I feel like I have made an investment, the weighting and balance with the kit 18-200mm lenses is much better than my 400d with the 28-135 EF and its much more intuitive than the 400D. In fact it's arguable that its behind the scenes complexity and range makes it a much easier day to day camera.
Its not a 5D mk2 I know, and photography for me is my hobby and £2k for a body is beyond my comfort range also I have realised I don't do video.
The other thing I have realised is that I will never like Nikon, don't know why I just don't, I think the industrial design of the canon's say 'Tool' much more than the curves and red flashes of the D90 and d300. They may be better camera's in most people's minds, but for me its canon all the way baby!