There isn't any clear answer. I had an A2, but sold it again. I think it's a pretty good camera, probably the best 8MP prosumer as of spring 2004. I can't really say that there were one sepcific issue that made me sell it again. I thought I could postpone getting a dslr a while by getting a good prosumer. Didn't work that way. Autofocus was too slow and inaccurate to compete with a dslr - although not any worse than other prosumer cameras.
It made me realize that I need two cameras. One (advanced) point and shoot/prosumer and one dlsr. And in that context the A2 wasn't right. I've recently purchased a Nikon 8800, and I'm happy with that choise so far (only a couple of days).
While the A2 probably was faster, at least in raw file handling the 8800 has a zoom range that suits my needs better. And this time I knew I wouldn't get a particulary fast camera - and decided to live with that.
So for the A2/A200 comparision. First, for focus speed and accuracy and lens performance you really have to wait for a review. What I'll say something about is the changes.
The big downgrade is the electronic viewfinder. A2 has the best one so far. A200 will have one that's no worse than other prosumers. Still, even if A2's EVF is best I can only see it as slightly more useful than other EVFs. It gave a slightly better picture, but it still wasn't easy to judge focus, and it's extremely difficult to judge the effect of e.g a pola filter. So the conclusion is that A2's EVF is nice, probably the best available, but still not good enough compared to a optical (slr)viewfinder.
I think the upgraded LCD (almost) compensate for the loss of EVF resolution. Slightly higher resolution, but more importantly is the improved tilt and swivel funtion. Also that it's possible to turn it towards the back of the camera for protection. The movable EVF of A2 was a feature I never used. When you have the camera in a difficult position it's much easier to use the LCD than the EVF.
I think these are the main differences. Tried the tracking AF on A2, didn't work well for me (missing on A200). I certainly appreciate the slightly smaller size and lower weight of the new model, but it's not a big issue.
The movie mode is slightly better on A200, but the highest res is only available with reduced frame rate, which makes it completely uninteresting to me. Real VGA mode with 30 fps is a bunus though (A2 was slightly lower res).
Another possible improvement is a faster processor. That's always welcome, but again - don't expect too much before you see a review.
So my conclusion si that A2 and A200 is about equal. Just different. If you prefer the old or new feature set is really up to personal preferences. A2 got quite a bit of bad press due to autofocus and image softness. A200 preumably have the same lens, but Minolta might have made some minor changes. I think that's the main issue you have to watch for, and only decent reviews can tell.