Starwood hotels are Sheratons, Westins, W, aLoft, and a few others
The card allows you to transfer points for airline miles 1:1 in most cases.
Points can also be redeemed for free nights. The "Nights and Flights" deal seems to be the best. For 60k pts you can redeem for 6 days/5 nights and 50k miles. With most other programs one would only get the airline miles.