Welcome to the forum.
I, as well as many members here, have the 20D. It's a great camera and should be a great fit for you, coming from an Elan.
Since you shoot with Canon gear already, another consideration should be the Rebel XT. It's a fair bit less expensive but it's not the camera that the 20D is. The XT is smaller (too small for me) although it can be fitted with a battery grip. The layout and controls are different. The 20D has the thumb wheel that the Elan has...that is a great feature.
The 20D has a more solid body while the XT has more plastic, although it's still not a toy camera.
The image quality is very similar, I think the 20D has slightly more pixels 8.2 vs 8.0 The best argument for the XT is that you can use the savings toward better glass.
Do you like to shoot wide angle? Both cameras have a 1.6x cropping factor. So the lenses you use on the Elan, will give a view as if they were 1.6 times longer. That's nice on the tele end but not so much on the wide end. Both the 20D and the XT can use Canon's EF-S lenses...which are made specifically for these 1.6 crop cameras. They give you a wider view for less than a real full frame EF lens would cost.
I've been very happy with my 20D, it's been great for me. I've even put it though some torture while in the rain forests of Costa Rica, and it's still working great.
If you're financially advantaged, the Canon 5D might be an option. It's basically the 20D body but it has a full frame sensor...so there is no crop factor and you get 12MP rather than 8. Of course, it's at least twice as expensive as the 20D.
One thing to consider...Canon may be announcing a replacement for the 20D in February at the PMA. There is a lot of speculation but Canon is pretty tight lipped so no-body will know for sure until the press release is out. You might want to hold out for the new model (if there is one) or you might be able to take advantage of a reduced price on the 20D.