Yeah take the time to develop your title tags carefully, making sure you have a good keyword foundation from which to draw and that every page has its own unique title reflecting the subject and keyword terms being optimized for.
I agree. From my understanding, Meta tags are not so important to Goolge but still somewhat important to Yahoo and MSN (who combined, have about 28% market share - not to be over looked).
The description tag should be used for exactly that - providing a brief description of what the site is about. As
gbonnet said, the description is used as a snippet on the SERPs so it's a good idea to optimise it, describe your content using similar keywords but keep it sounding natural. Regarding length, I don't think there's a set rule here, just that if it's too long it will be truncated by Google - I think somewhere around 135 characters is optimal.
Regarding keyword tags...the way I see it is why not use them. But care should be taked not to stuff. Referring to your question Dotwebs, there's no need to repeat words. As far as I know there's no maximum as such, use a sentence-worth if you're unsure. The above keywords could be tagged something like:
website design, web development, internet marketing, online advertising
I definitely wouldn't repeat the words for the title tag. Raul said he's experienced a noticeable change in "the page title...more importance than the meta keywords or meta description...". And as pointed out by Hafsoh, have a different title for every page - have a maximim of three keywords/phrases per page and optimsie the content and the title around those.
Ideally, the title should contain a mixture of the three main keywords/phrases but used minimally if that makes sense. The more words used, the lesser the value assigned to
each individual word. So no repeats if possible. And the primary keyword(s) should be as close to the beginning of the title as possible (keyword proximity) ...and no "stop" words like "to", "and", "of" - these are assumed words by the spiders so no need to add them. Using Dot's words above, the title tag could be something like:
Website Design | Developement | Marketing Online
The spiders will understand "website" as "web" and vice versa. Maximum length for title is said to be 75 - 85 characters though some believe it's 65. I'd go with the minimal-words rule but ensure that it doesn't exceed 75 characters (if possible).
Hope this is useful Dotwebs,
Rita