Playing By Googles Rules
As the undisputable leader in search engines, Google places a very high importance on the quality and relevancy of its search results, especially now that the company is public. The know that in order to keep the shareholders and users of the engine happy, the quality of returned results are vitally important. Because of this, doing the wrong thing, purposely or unintentionally could result in a severe penalty or even get you get you banned from the listings. Below is a quick list of ideas to consider when drafting your search engine optimization effort.
Link PR is becoming a popular topic among seo companies, however whether or not incoming/outgoing links still play an as important role as they used to, it still considered a"blackhat" technique that can and most probably will lead to a ban or penalty from Google.
Stuffing your pages with text to small to read, same colour as the background, or using css to push the text of display for the sole purpose of loading your pages with content rich keywords and copy will even get you given the exact penalties as hiding links.
The practice of using browser or bot sniffers to serve the bots another page then your human visitors may see. Loading a page especially for a bot that a human user might never see will most certainly get you banned from the listings.
Submitting your domain and pages is also a big thing to steer clear of. Be certain that you check if your domain is listed already in the search engine you're submitting too, if it's... proceed to the next.
Be careful who and even what it is you are linking to. Links in to your website won't hurt, even Google knows you can't control your hyperlinks in. However you can certainly control what you link to. Link farming has always been a bad apple in Googles eye and must be avoided at all costs. Google also suggest your link pages shouldn't contain more then 100 links, suppose anything greater then 100 links on a single page will get you classed as a link farm and avoid doing this.
This is similar to cloaking pages. The tradition of having one page packed with your choice key words that just re-direct to another more"user friendly" page is also a huge issue for Google. My customers get offers all of the time from other search engine optimization firms offering these sorts of"services". If you get these deals, avoid them at any cost.
Same Content on Multiple Domains
Google looks at domain IPs, dates that they were enrolled, etc.. Having multiple domains serving exactly the same content is a no no too. This also applies to serving the exact same content multiple times on different pages, sub-domains and forwarding multiple domain names to the identical content.
Lots of the above techniques apply to most search engines. By following a mind set that you're building your pages for the human users and not spiders, you can insure you'll find the most important things from your website: Qualifying clicks, links and a higher ROI.