I really do love this camera. It's unlike anything I've used before. However...
The menu system is absolutely rediculous. It's so much harder than older models were. I had a D30 before and the menu system is the easiest thing ever. It actually made sense. You would hit the menu button, then use the dial on back to move through. Then there was a select button in the middle of the dial. Easy!
Now, you have to hold down a button the left while using the dial to move around. Now that select button is on the left with all the other buttons instead of in the middle of the dial. Why? You can't do anything with the dial now without holding down a button on the left. Why? What a hassle. You can't even scroll through the pictures you've shot without having to hold down the select button at the left the entire time you're scrolling with the dial. This is just plain stupid.
I know it doesn't sound like much, but I have better things to do when I'm on a shoot that stop and think about all the proper procedures for changing a setting or looking at pictures I've shot. If I had any hair left I would have ripped it out by now. It's also much harder for me because I shot so many years with that D30's logical set up. If I'd never been exposed to what Canon can do when they're thinking, I guess I wouldn't know what was wrong about this set up. It's like surfing to a web page that's overly complicated for no apparent reason. It's irritating.
Also, since it is a full frame camera I've been getting a lot of vignetting in the corners. This happens a lot when I have a filter attached to the end. Neither the software included or Photoshop CS2 really does that good a job of getting rid of it. That's a little dissapointing.
My only other beef is the lack of a small built in flash. Yes, yes, pros don't use such things. Well, that's not true. I used the flash on my D30 a lot. There are occations when all I need is a little bit a back fill. I really don't need to strap that big speedlite on the top. Since I use this camera for everything, not just the pro stuff, sometimes it's nice to put on a small lens and use a little built in flash.
Plus, you thought the camera was heavy? Try putting on a nice heavy lens and then attaching a huge speedlite to the top. Not only is it heavy, it looks rediculous. You might as well where a big sign that says "Hey. Come over here and ask me some questions. Or, better yet, just stare at me for a while then rob me when I leave."
Overall, you will LOVE this camera without question. There is nothing else like it. It does so much so well that the things I mentioned are not too big a deal. I just thought you might like to know about them. Plus, if anyone from Canon is reading, please fix those menus! Of course, it's too late for me. I'm going to have this camera for so many years fixing those menus won't make any difference. By the time I'll need a better camera I'm sure we won't even need them. We'll be able to take pictures by just pointing our fingers at something.
I'd mention the good points but I really don't have to. If you're wondering wether a it has a feature you like: Yes. It does. How well does it... Answer: Very, very well.