You gotta go with the Canon SD's. Those are terrific cameras. I have an SD400, 5.0MP, 2in screen ... and I'm never going to another brand. This was one of the best purchases I've ever made.
The SD450 has the same guts, but a larger LCD.
I tried (and returned) the Sony T line. Those
were the slimmest cameras at the time (June 05), but the picture quality sucked badly ... it was plagued with red-eye issues too.