You said it yourself. Time isn't doing a good job of picking people, and resort to doing that. For this year, Hurricane Katrina would have made a better choice than Bono and the Gates (since Time has shown they will choose non-people for "Person of the Year"), but if Time really wanted to limit it to people, they could have chosen someone like Condoleeza Rice, Cindy Sheehan, John Roberts (maybe have Roberts share it with Harriet Miers, or John Bolton, as opposite ends of the political coin), or Karl Rove.
