SlimKim - 3:18 am on Mar 13, 2007 (gmt 0)

I may have stumbled onto the answer to my own question. It's as good an explanation as i can find.

It may be that some trademarked keyword serch terms are removed at the trademark holders request.

When i use the Google Keyword Suggestion Tool for the search term: dell, i get the following results - We're sorry, but we're unable to generate relevant keywords for this keyword. Please make sure you have entered the keyword correctly. Or, enter another keyword into the box to see related keywords.