We've had five "Jeopardy!" guest hosts so far, and some have definitely been better than others. If you're wondering how they've been doing in the rankings, here are the numbers so far: Ken Jennings was the first person to take the podium following Alex Trebek's death, and so far, he's done the best, with an average Nielsen rating of 6. "Jeopardy!" producer Mike Richards is second with a 5.9. Aaron Rodgers is third with a 5.6 . . . but that's after only one week. His second-week ratings weren't in yet when the list was compiled. Katie Couric is next with a 5.5. And Dr. Oz brings up the rear with an average rating of 5.1. I'm not surprised by those numbers. I think Ken did the best job, and Mike was a close second. I thought Dr. Oz was not good at all. I felt like he was condescending to the contestants. Anderson Cooper just started on Monday with his two week gig, and I think he's doing a good job. That's no surprise though since he's hosted game shows before. And coming up after him is Bill Whitaker, then Buzzy Cohen for the Tournament of Champions, then Mayim Bialak, then Savannah Guthrie, Dr. Sanjay Gupta and Joe Buck. That's the complete lineup so far. Who have you liked the best so far?