A while back I received a solicitation for this card which included the 5% credit on a balance transfer. I wrote a check for $50,000 (the credit limit) to my bank and earned a $2500 rebate, which I used on a Blazer. I double dipped with upromise for $150 on a new GW purchase. And I triple dipped since I earned a spread on the $$ in the bank (INGDirect) as the interest earned was greater than the promo interest rate charged. All in all, it was nearly a $3000 deal "value".
It did take the billing cycle to get the rebate credited and at upromise you do have to register 30 days before you buy the vehicle.