Thanks for the tips. I've chosen the Canon Powershot A650 IS against a few better judgements:
- 4 AA batteries! But I'll use high quality rechargables
- Bulky/thicker. Still small and grip is nice.
- No review on dpreview.
- Twice the cost of A590 and A720.
- "Cheap build" says dpreview.

But there are a few great selling points:
- Bigger CCD. 1/1.7 instead of 1/2.5.
- Vari-angle LCD to help the awkward shots I often take.
- 12MP matches Rebel XSi for image size consistency.

I'll get an Elph for my sister (her film P&S finally died), so maybe I'll fall in love with that instead. Thanks again for your help.