Keith Olbermann is never better than when he's talking about someone he respects (perhaps because there aren't many of them). Last night was one such occasion, when Olbermann devoted an entire segment to David Letterman's announcement of his impending retirement. "All I keep thinking," Olbermann said, "is I'm watching Babe Ruth telling us he's going to stop playing baseball."

The metaphor gets drawn out further, and works to varying degrees. But there's no disputing that this is a heartfelt and surprisingly comprehensive summation of Letterman's career, culminating in an anecdote of Dave at his funniest and angriest best—that 2008 show when John McCain blew off the Late Show for Katie Couric, and Olbermann, as a fill-in guest, had the best seat to watch the evisceration go down.