I believe 5 is the max.
I'm at 3, but will be back to 2, before I try for my next card likely.
5 Upon opening your Card Account, and by February 15 of each subsequent calendar year it is open, you will receive from Starwood credit for 2 stays toward your Starwood Preferred Guest Elite status and credit for 5 nights toward your Starwood Preferred Guest Elite status. This benefit is limited to one annual 2 stay credit and one annual 5 night Elite status credit per Starwood Preferred Guest Credit Card account. You will not receive additional 2 stay or 5 night Elite status credits if you have multiple Card Accounts. Credits and status are subject to terms and conditions of the Starwood Preferred Guest program.
I read it on their website. Is that mean you can have 7 free night every year ????