If you don't use higher ISO speeds much and need the extra pixels, then it may be worth considering. I really don't see any big benefit to upgrading though.
The A700 would be a much better upgrade.
I'm really just getting into using manual mode, and I've been playing with the higher ISO's, and I just did save enough fro the A100. I don't have enough for the A700 and this is just a hobby and my wife would kill me if I spent that kind of money.
I could use a walk around camera, what does anyone suggest? I really like/need image stabilization.