Patrick_Taylor - 10:58 am on Jul 18, 2008 (gmt 0)

My thinking is that a unique META DESCRIPTION is more important on pages with little unique descriptive text (eg: product pages). In my experience of this, the snippet is then likely to contain a fragment of the description plus some other text from somewhere on the page, perhaps even the footer.

But for more descriptive pages, omitting the meta description is more likely to produce a tasty snippet, leading to more click throughs for a bigger variety of search phrases. Perhaps this is Wikipedia's thinking too.

Whether this affects actual ranking, I don't know.