I agree with everything everyone said: BUT A WARNING (and an alternative):
I travel alot - and I mean more then you can dream of: Last year I was at 220 days in Europe. This year, I have been home 15.
I got one to earn points - and it worked! It saved TONS! One time my expense check was late - so - we paid 3 days late! The interest rate shot up to 27%. Card was immediately cancelled.
I had put 150K USD in 18 months of travel with ZERO missed payments. And, paid in FULL each month. One time, 3 days late and WHACKO! Ok, MY FAULT! But, I figured I could call and explain. Someone who racks up 150K in travel should get a break. No, not at all.
As long as you pay it off - a wonderful product - but dont EVER be late!
My Alternative: If you travel alot and spend money on hotels the most lucrative program (and their is no second) is the Holiday Inn program. They have a ton of hotels (worldwide) and many different choices (Intercontinental, Crowne Plaza, HI Express, Candlewood Suites, etc.).
The bonus point structure is second to none. They always have promotions and you can find little known ones by checking flyertalk.com.
While I travel 200 days a year - the town I stay in and work in Holland has no Holiday Inn - so - to get my points I check out on weekends and drive somewhere that has a HI!
If you STUDY the program - it is a ton more lucrative then the Chase program.