Early Buy Back

I just got a letter in the mail telling me that Beverly Hills BMW is authorized to buy my car back earlier than the termination of my lease (lease ends in 10/07). I think the catch is I have to get another bmw. They're allegedly buying back cars early b/c there's a "huge" demand for used vehicles. So what's everyone think? Total scam to make more money off of me or is this legit for people who want out of their lease early?