In a stroke of serendipity given our recent conversations here, Simon Joinson at dpreview has posted a primer article on digital point-and-shoot noise at higher ISOs. (He calls 'em "compact cameras," probably a better term.) Conclusion? Basically that only the Fuji F10-F20-F30-F31fd series offer usable high ISOs in a compact camera, with good performance to ISO 800 and a usable (if barely) ISO 1600—and pretty much everything else is marketing hype and wishful thinking.
Although it's discontinued, the best buy in this series, the F20, is still available from many retailers. At only $142, it's almost $100 cheaper than the newest F31fd ("fd" stands for "face detection," which might be useful if you're unable to recognize faces for yourself. Forgive sarcasm). That seems very cheap for a walk-around pocket camera that will give you a real ISO 800.
Do read the whole article if you're thinking of getting a point-and-shoot / compact camera—it's sure to be the definitive word on the subject for the foreseeable future.
Posted by: MIKE JOHNSTON with thanks to David Bennett