Sgt_Kickaxe - 2:31 am on May 13, 2012 (gmt 0)
Essentially in these cases, Google is trying to find "deep" content than normally doesn't see the light of day.
I beg to differ, I believe they are looking to see if the page returns dynamic content based on the parameters requested. Spammers often key on queries and keywords to create infinite numbers of pages dynamically and Google doesn't like that. Even if you're not a spammer you need to be aware of how your page responds to such requests, they essentially should not change regardless of parameters added(if they exist) or should return the proper error code if they do not exist.
e.g webmasterworld.com/google/?apples=oranges should return the EXACT same content as webmasterworld.com/google/ since webmasterworld.com/google/ exists. To Google it would mean the parameters had no effect(a good thing).