You are right. The NEW GM Card has different redemption limits for different GM models, with a minimum of $1000. The OLD GM Card lets you use upto $3500 in rebates accumulated over seven years (at $500/yr).

But the NEW GM Card has no limits on how much rebate you can accumulate in a year, whereas the OLD card has the $500/year limit. So if you are a heavy charger, say $30-$40K per year, you can accumulate $1500-$2000 in rebates in a single year. Add that to the current $1000-$3500 in GM Manufacturer's Rebates being offered plus the heavy dealer discounts, you could reduce your new car price very significantly.

IMHO, you should switch to the NEW card only if you are a heavy charger. If you only charge about $10K or so per year you will be stuck with the smaller redemption limits with the NEW card. Remember, once you switch from the OLD card to the NEW one, you cannot switch back.

P.S. I have the OLD GM Card. I chose to keep the OLD one as I only charge about $15K per year. Once I reach about $450 in rebates (on total charges of $9K) on the OLD card I switch to the no annual fee HILTON AMEX card (I also use the HILTON AMEX for all HILTON stays). If some merchant doesn't accept the AMEX card I use the GM Mastercard to earn the remaining $50 in rebates (on $1K charge) for that year. I also make sure that I accumulate the remaining $50 in rebate before the end of the card year.

Hope this helps. Good luck!