David Letterman's retirement announcement has left everyone wondering who will step into his shoes as host of "Late Show" on CBS.

Many media pundits think Craig Ferguson is the heir apparent to Letterman, considering that David produces his "The Late Late Show."

However, if the scuttlebutt is true, and Letterman stepped down because younger and more social media friendly hosts were taking his viewers, Ferguson may not be the wise choice. Besides, Craig seems more content in the later slot, where he can do more stream of consciousness monologues that may not play well at an earlier hour.

Craig Ferguson's "The Late Late Show" is produced by David Letterman's Worldwide Pants production company. (Photo: Getty Images)

Others are speculating the replacement may come from current hosts swapping networks. Conan O'Brien's TBS contract will expire at around the same time Letterman plans to leave CBS.

Jay Leno is immediately available, and his older demographic may fit CBS, but David may retain production rights to the new show, and there's no way he's allowing his arch rival to step in.

Jimmy Kimmel is also on record as saying he would be honored to replace his idol, Letterman, once his ABC contract runs out.  Would either of these guys seem a good fit? O'Brien's show hasn't exactly garnered big numbers since he was forced out at NBC, and Kimmel strikes me as a loyalist, who has no real reason to bolt ABC, who has continually given him prime time slots to promote his show.

Jimmy Kimmel has admitted that David Letterman is his role model. (Photo: Getty Images)

It also comes as a interesting coincidence that E! Network's Chelsea Handler announced this week that her show will be leaving that network soon. The timing seems almost perfect for Handler to move right into either Letterman's spot, or Ferguson's, if he moves down into the earlier slot.

My only doubt surrounding Handler is she doesn't seem the type to give up the creative control necessary to fit into the network business model, if there still is one.

On Facebook, several of my friends had some interesting suggestions, including Tina Fey, Chris Rock and Elvis Costello.

Fey would be a great choice, but I'm not sure she needs the grind of a daily talk show, given the success she's had behind the camera as a writer and director.

Costello was brought up because of the great job he did sitting in for Letterman when he was going through his heart surgery a few years back. Whether he would give up his musical touring schedule to do it is another thing altogether.

Rock is an interesting idea. Late-night talk shows have long been lacking in diversity, and Rock has a broad audience base that transcends color, so he would be a great option. It wouldn't hurt to ask him, but I doubt he would do it.

Who do you think will take Letterman's place? Who do you WANT to see in his place? Let your imagination run wild and let us know in the comments.

Here's a look back at the first Top Ten list Letterman ever did.