It appears that you haven't yet touched Chase Bank or Bank of America.

• B of A offers 25K Alaska Airlines miles for minimum purchase, first year annual fee waived. Alaska miles can be used for flights on America, Hawaiian, and many other airlines.
• Chase offers United and Continental Airlines miles cards with good bonuses, and its Preferred Sapphire card. They are touchy about issuing too many cards at once, so I would stretch applications for these out. The general buzz is 6 months between applications, but many report that the time is much less than that. Since Continental and United are merging, I am assuming that the United card will continue to be offered and the Continental card will be dropped. So I would do the Continental one first. The Sapphire card transfers its points to Continental. I suspect that Chase would be less sensitive about the timing for this card, since it is not a true airline card and since they seem to be pushing it hard. So I would do it second. Continental and United are Star Alliance carriers. In my opinion, the Star Alliance is the very best of the airline alliances for actually getting a ticket.

American Express offers many cards, some with mega bonus Membership Rewards points and first year annual fee waived. Those points will transfer to Continental (and Delta and many foreign airlines). That Continental relationship ends September 30, 2011. I would do this one right away. Amex usually permits 3 Amex cards, so your Starwood card should not interfere with getting a Membership Rewards card.

U.S. Airways offers a card with a bonus worth the first year annual fee. It is a Star Alliance carrier.

All of the airline and American Express offers I mentioned are listed and fully described on my website below on the Credit Cards > Annual Fee Cards page. The Preferred Sapphire card is listed on the Credit Cards > Bank and Other Travel Cards page.

And we haven't even started with the financial and other offers. You might want to look at those, especially the brokerage offers, to see which you want to accept, before planning which credit cards to get. Or, just assume you will become as addicted to this stuff as are we, and go for everything you can get, assuming all points and miles will be used somehow, sometime.