good article on how to set up your site for google SEO http://googleblog.blogspot.com/2007/01/controlling-how-search-engines-access.html
I hope he'll continue the article with an explanation and endorsement of the recently created "NOODP" tag. Few webmasters know about it, but it's a Google/Yahoo! sanctioned tag that prevents their SERP's from using your ODP (Open Directory Project) snippet. The ODP (aka DMOZ) is horribly under-staffed and under-resourced -- hence many old-time websites have descriptions pulled from there that are 5-8 years old and written by someone outside their company. Better to control the SERP snippet yourself than rely on something like that