META tags and SEO
It's easy to despair about some of the dodgy practices (or sheer ignorance) on the part of web developers today, but the reliance on META tags (or metatags) to do search engine optimisation borders on negligence. Don't get me wrong, you can put metatags, specifically META-description and META-keywords tags, on your site but they're of no value whatsoever. They don't get you anything: search engines don't use them as a means of index ranking (they don't get you anywhere in the search results) and directories do their rankings by actually reading the page itself rather than taking your recommendations on what a page means.
The reason this is so is very easy - it's trivially easy to game the system by stuffing relevant (or irrelevant) keywords into meta description tags, sit back and let the search results roll in. So easy, that during the 90's the ecommerce early adopters (those purveyors of shapely, naked bodies) did this with reckless abandon. On a course I taught in 1996 I used to demonstrate this to CEOs, marketing directors and others who wanted to know about this new interweb thing using Hotbot, the search giant du jour of that time. They typed "Ferrari" or "Lambourghini" into Hotbot and sat back amazed when 8 of the 10 results came back as the aforementioned dodgy sites with no content at all to do with Italian supercars.
Of course the search engines quickly realised this and changed their rankings algorithms. Sadly, many web designers and developers haven't moved on from 1996 and are still satisfied in giving their customers a widget to add metatags, telling them "this will do their SEO for them." Shocking, but still widespread.
But, hey, don't believe me - listen to Google's Chief Search Engineer, Matt Cutts on the subject:
Now, in the first paragraph I said "almost" no value but as that's a very complex, heavily caveated and qualified argument, feel free to read on having been warned: the META-description paragraph, if present, is featured in the snippet displayed as the search query result for a page by most search engines, including Google, if the META description tag exists. Otherwise Google displays several relevant snippets of text where the query keywords exist. I have to say a "well-written META-description" borders on clairvoyance - knowing ahead what someone will search on and find you page - but if you know this, you won't be needing META tags to get search results - you'll rule your niche on Google. For the above reasons we actively recommend our customers not use META keyword or description tags. At best they're a waste of valuable work time. At worst META description tags in search results can mislead their customers.