Applied for this on Monday and found out I was approved today for a limit of 10K!!! It will be one of my highest limit cards. Once I get this card I'll cancel my Discover Platinum. I think Discover Gold is a better card if you don't spend that much because you get a full 1% cashback for purchases of $2,000 or more. Plus it's a really good looking card.
before you cancel your platinum card, you might want to see if Discover will merge the accounts, so your credit limit would be even higher. I know other cc companies do this, discover might.