I have a Nikon D3000 - it was a good entry-level DSLR but now I'm looking for something a little (A LOT) faster. I'll be watching this thread for suggestions!
I use the Canon 5D Mark II. Love it! If you want to see some pictures, I just started a photo blog, http://365photo.tumblr.com. Hopefully I can keep the photo per day commitment if my laptop holds up.
I have a Nikon D7000 and an old dinosaur of a Nikon D50 -- looking to add a used D700 (or new D800... crossing my fingers) to my arsenal by the end of the year.
I have a Canon 40D, but I sure wish I could afford to upgrade, but I am happy with it except I wish I could afford some other lenses.