Where to start... so many new toys.
The biggest draw for me to this is the new AF system. While it certainly smashes everything short of 1D class in their own range, how does it compare with Nikon's "51 point" system?
iFCL is also somewhat interesting. With the either of my current cameras, I find I need to be extra cautious if shooting subjects with colour contrast, such as vivid flowers, as it can be easy to clip a colour channel. If that prevents this from happening so often that'll help too.
The viewfinder grid sounds a bit like a "me too" feature copied from the other side, but I wouldn't say no to it.
The rapid 8fps at least is offset by 150k shutter rating, so maybe I wont burn it out in a year
On high ISO noise, I'm not sure about the ISO1600 one compared to 50D, but certainly at ISO3200 and above, it is much better, as it does not exhibit a banding pattern.
One curious thing though, the press release says kit is with 28-135 IS USM zoom? That sounds like an odd choice for a crop sensor body.