[rtrombone]

From their Bonuses/Specials page:

Paradise Loyalty Club
Beginning September 1, 2004 players at BetJamaica are enrolled in the Paradise Loyalty Club were they will receive a free bet for every 100 sports bets placed. This free bet is calculated on the players average bet size, bets will be placed to a maximum $200 free bet. To redeem Loyalty rewards, please call 1-800-288-9069 between 12pm to 4pm EST, Monday through Friday.
** Please note: That only a maximum of 10 free wagers can be redeemed in 7 day period. Wagers on both sides of a game are not allowed. No correlated or manipulated wagers will be tolerated. If an account is correlating or manipulating loyalty wagers it will result in all existing and future loyalty wagers to be void and account no longer eligible for the club.**

This must be what you guys are talking about. I've been collecting my free bets as I go, but judging from the size of the bets you guys have received, they don't expire.