The answer also depends on your spending patterns (daily life) and the kinds of hotels you typically stay in while using your own credit cards.

I have the Hilton Surpass and also the Chase Marriott Premier Visa and Starwood Amex. Corporate travel has to go on the corporate Amex, so I use my personal cards only for personal stays. Budget-wise, the Hyatt and the higher-end brands in SPG are outside my usual price range when I'm paying: Hiltons and Marriotts are a better fit. I haven't been that thrilled with Choice or Priority Club hotels/rates.

I find the annual fee for the Premier Visa worth it, in part because of the one night-stay certificate that comes with it. (The first year Category 4 certificate isn't that helpful unless you're staying outside the big U.S. cities, but the Category 5 gets you into a decent range of hotels. Last year, we used ours at the Cairo Marriott.) Automatic Silver status gets you slightly better treatment in hotels (although no lounge access).

I use the Marriott Visa for restaurants (including our cafeteria) for its 2x points, the Hilton Amex for groceries and drugstores, and another card (currently either the BA Visa or Presidential Plus Mcard) for my other purchases. I've got Gold status with Hilton until 2012 so I'm not using it a lot, but I'll start using it again in 2011 so I hit at least the $20,000 spend to retain Gold.

I haven't been that thrilled with the SPG Amex, in part because I find the SPG point accumulation methods limited and I don't stay that often at SPG hotels, so I have never really built up a big stack of SPG points (and that seems to reduce the incentive to accumulate more). By contrast, I accumulate MR points through the credit card, the occasional hotel stay and through Marriott's internet shopping portal, which functions pretty well. So that seems to keep me motivated to use the credit card fairly often and accumulate more MR points.

My choices aren't necessarily the most rational ones, if you look at the pure economics of the cards, but they work for my spending and travel patterns.