This one is up for debate and borders on the fringe of black hat SEO. For those of us wanting to keep our SEO jobs, Google does a great job in telling us what they considered cloaking.

From my perspective, I believe any content presented to the visitor should be the same as to a SE spider.

Here is a breakdown of the of the definitions as posted on Google’s Webmaster Central Blog:

Geolocation: Serving targeted/different content to users based on their location. As a webmaster, you may be able to determine a user’s location from preferences you’ve stored in their cookie, information pertaining to their login, or their IP address. For example, if your site is about baseball, you may use geolocation techniques to highlight the Yankees to your users in New York.

The key is to treat Googlebot as you would a typical user from a similar location, IP range, etc. (i.e. don’t treat Googlebot as if it came from its own separate country—that’s considered cloaking).

IP delivery: Serving targeted/different content to users based on their IP address, often because the IP address provides geographic information. Because IP delivery can be viewed as a specific type of geolocation, similar rules apply. Googlebot should see the same content a typical user from the same IP address would see.

Google also created a video presentation of these bad, bad strategies.

Cloaking: Serving different content to users than to Googlebot. This is a violation of the webmaster guidelines. If the file that Googlebot sees is not identical to the file that a typical user sees, then you’re in a high-risk category. A program such as md5sum or diff can compute a hash to verify that two different files are identical.

I’ve always heard of these shady techniques and wonder why rogue SEO’s play this game. They are jeopardizing their clients and more importantly their reputation.  Just create unique, compelling content that will increase relevancy, ranking, and ultimately-conversions.