It seems that Metatags these days when it comes to SEO is losing it's prominence and effect on rankings. This ofcourse is due to google mostly ignoring all metatags. So what metatags matter and what doesn't?

<Description> metatag - Ignoring the giant loss from google, metatags still has some value in other search engiines like MSN and Yahoo. Another importance that it might appear in your search listing, providing some measure of influence on the viewer.

<Keywords> - Same thing as above. Of course, as with all keywords that you put into the metatag, don't put anything that you don't have in the page's content.

So remember, don't fall into the trap of thinking that it's better to stuff all sorts of keywords into metatags to 'cover all the bases'. Target specific keywords about 10-20. Put in too much, and it 'de-optimize' rather than optimize the traffic coming your way (better than putting nothing, but not as effective as it can be). Especially so when you don't match it with relevance to page content.