Don't make it promotional, make it informative.  You're not trying to sell your product on wiki; wiki is an informational source.  Provide information about when your company was founded and use neutral terminology about the products your company sells.

We tested the waters with wiki by adding a single external link to http://www.hipepc.com under the category of "carputer" and have received 5,000 additional hits and a potentially large offer from an automobile manufacturer inside of a week for one tiny little link in a category that's not even our main focus.  We'll be tossing up our company profile within the next week or so.

Wiki works when you view it as an external "about us" page that focuses on the whos, whats, wheres and not on the hows and whys.

Good luck and let us know how it goes!

-Rich

"Make a myspace page for your business, as well as a wikipedia page!"

How can you post a wikipedia page that would help your site - they will kick any promotional sounding article out within 24 hours...?!

I've noticed that Google updates its index every month or so for most sites, regardless whether or not your robots or metatags tells it to come back in 7 days.  You'd never expect it, but Google is a pretty awful search engine, despite its popularity. 

Meta tag keywords have no relevance in Google first of all. 

Also, the backlink search on Google is horribly broken.  If you have the Google Toolbar and your site isn't showing backlinks under link:http://www.yoursite.com/, try doing link: http://www.yoursite.com, the difference being that you put in a space after 'link:'.  Also try link:yourdoman.com and link: yourdomain.com.  Alot of folks freak out when they don't see their backlinks, including me.

Even still, more backlinks show up in MSN and Yahoo.

Titles are very important, meta tag descriptions matter quite a bit as well. 

ALT TAGS HELP!  For example, if I have a picture of a gaming pc with a link to the gaming pc page, I stick in an alt tag of something like "buy gaming pc, gaming computer".

Another trick is to stick a couple of commonly misspelled words into your meta description.  Like 'gmaing pc' ;)

Arguably, adding new content supposedly boosts your rank slightly, but I can't say for sure if that's the case. 

Google page rank is a joke though, don't put much stock and store into it!  Even Google says it's for 'entertainment purposes only' as it's only updated a couple times a year and the criteria for boosting the 1-10 pagerank isn't very clear.

The age of a domain also seems to matter, which is entirely unfair, as it keeps new domains down.  But no matter how you optimize, it will probably take a few months before you see a good ranking.  Link share programs help and hurt, depending on the relevancy and reputation of the links.

Couple easy things to do: Make a myspace page for your business, as well as a wikipedia page!  both are incredibly popular links and show up on Google FAST.  Also, peddle your wares on Ebay or Craigslist, both are also pages that show on Google almost immediately as well.

That doesn't even scratch the tip of all the SEO tricks out there, but it's a good start :D