Jason, what got done to you is unfortunately very common. They look for domains that expired WITH a lot of previous traffic to that domain.
When they find an expired domain that had traffic, they register the domain (like $9), and put up an advertising site that by keyword has links to similar topics to the traffic the domain had, and they get paid by the click, they are milking a prior owners traffic. Usually out of India, it's very cold and all done purely by the statistics, and they make enough money with this that rarely to "they" allow the domain to lapse again.
That said, I'd suggest going to GoDaddy.com and put in a "backorder" for the domain, so that if it ever does lapse again you would be first in line to get it back, an automated process you wouldn't even have to chase up.
It's happened to a lot of great people. Very infuriating!
Frank H.
