I spent Sunday morning in the camera shop, at severe threat to my wallet.
A big thanks is in order to the (temporary) manager as she let me sit in the corner with a 20D, a D70 and my 1G microdrive - and left me alone !!

They had a 20D in stock with the kit 18-55 and I spent a happy hour with it, and the manual. Technically fantastic, except for the lens.
When I tried manual focussing and the front of the lens slopped about 1mm in all directions off axis, I wanted to scream in frustration, I could move a point in the image from one side of the central focus point to the other !
I tried both that they had on stock and they were identically sloppy, so it's possibly just a design thing.
Then I tried the Nikon D70 they off the shelf and almost fell about laughing when the lens movement was worse than the Canon !
I'd say the 28-200 GT APO built into my Minolta A1 was better built than the kit lenses.

I loved the 20D, but found the controls awkward. Provided I use Tv or Av mode, then it's fine. What I had real problems with was aperture control in manual mode. I really couldn't operate the control dial for aperture while holding the camera securely, I didn't find enough body on the left hand side to hold on to.

I also found my right hand hurt after holding it for a while, mostly in the ring and little fingers where they wrapped around the battery housing.
Now I know the D70 is lighter, but when I picked it, I just said YES! and grinned.
It just felt good in my hand, where the Canon felt awkward.
The shape of the battery housing is very different, slightly curved instead of the squarer shape of the 20D. Most importantly narrower on the front edge where my short fingers actually fitted around the grip.

The two control dials on the Nikon are arranged more like my A2, one for the finger, one for the thumb. Much easier to use for me, and fell to hand neatly.
They didn't have a manual for the D70 (was she biased towards selling me a 20D?) so I had to work it out by trial and error.
Most of the control functions were obvious. Far more discoverable than the Canon multi-function buttons. I particularly liked the flash adjustment on the flash pop-up button, an obvious place for it. Far better then the Canon's press and hold some other button and then twiddle to set the flash.

The Nikon menus were easier to use than the Canon, but seemed not to have as many settings in the menus. But without the book to guide me, I'd never have fathomed the cryptic Canon custom options. I reckon it's honours even there vs the Nikon CSM.

20D flash and its fill-in performance seemed better than the D70 to me. I think (but didn't measure it) the 20D flash is a little farther from the lens than the D70.
Setting up the flash and attempting to balance it against daylight outside the shop defeated me on both cameras. But that's no surprise as I think it was in fill-in mode but couldn't be sure. Seems the NIkon was actually in red-eye mode according to the EXIFs. I suppose that's an issue in itself that I couldn't tell what mode the flash was in on either camera.

All in all today made me appreciate how good the A2 actually is in telling me what's going on and making it easy to control. And how poor it is at focussing and how slow it is to power on, nothing I didn't know already but the 20D made it obvious

So, am I going to buy the NIkon?
Absolutely not.

Well. am I going to buy the Canon?
No way.

The D70 autofocus felt far too slow for motorsport.
The burst mode was slow on the D70 too, though it was almost twice as fast with my 40x WA lexar than with the microdrive. The Canon however was just fantastic even with the Microdrive.
White Balance on the D70 was all over the place. OK so the shop has fluorescent and daylight, so it's a bit of a challenge. But the 20D was consistent from shot to shot.
The 20D was just not feeling right in my hand, it's subjective I know

There was nothing available that was comparable to the 20D to try, the D70 doesn't feel in the same league - it is more like a 300D to me, a capable camera but not what I'm after.

I'm now waiting for the D2X
Because while the 20D does what I want now, my hands don't fit the camera !
A real shame, because almost everything else about the camera was right.

So for now, wallet intact.