I really like the SD Powershot cameras, because they are very small and have image stabilazation. Something you might want to take into consideration in making your choice is that the SD Powershot line has had some changes in the zooming and telephoto choices. Specifically, look at the review for the SD700 and notice that the lens range is 35-140mm:
Canon SD700 IS Digital ELPH Review: 1. Introduction: Digital Photography Review
Now look at the SD800 Powershot and notice that the lens range is 28-105mm:
Canon SD800 IS Digital ELPH Review: 1. Introduction: Digital Photography Review
The SD800 will allow you to take a wider angled picture due to it's setup. You need to decide which is best for you.
You might want to look at the SD850 as well. It went back to the longer lense range that the SD700 has. Truthfully, there were some problems with the shorter lens range that resulted in the SD700 being viewed as better than the SD800 in some tests.
You should also read Ken Rockwell's take on the SD700. Hit the link and scroll down till you get to the discussion of the SD700.
Summer 2007 Camera Guide
For the price, the SD700 is hard to beat. Indeed, it might be better than the later SD Powershot Cameras that followed it.
Above all, make sure your camera is a Canon and that it has image stablization.
Good Luck.