Hi there karebear02msu,
Welcome to the Q&A Board! Check out these professional reviews:
http://www.imaging-resource.com/PRODS/SD400/SD4A.HTMhttp://www.dpreview.com/reviews/canonsd400/And here are some user reviews:
http://www.dpreview.com/reviews/read_opinions.asp?prodkey=canon_sd400Sounds like a great camera. Just remember, every digital camera has pros and cons and I know of no model that is "perfect," no matter what the cost. If the SD400 has the features you want and the price is right then, based on what I've read, I wouldn't hesitate to get it.
One of the things I like about Canon ultra slim and small digital cameras is that they still have a viewfinder (unlike so many others that only come with a LCD).
Hope this helps.
Related reading: Digital Camera Buying Charthttp://www.digicamhelp.com/choosing-a-digital-camera/index.htm