Here’s a quick look at some of the casting announcements made recently:

ER: George Clooney won’t be the only cameo to keep an eye out for in the next few weeks. TV Guide reports that vet Sherry Stringfield (Dr. Susan Lewis) is now scheduled to make a return to County General as well. No details about her visit have been revealed.

Meanwhile, it’s been announced that Gilmore Girls’ Alexis Bledel will be appearing in the April 2nd two-hour finale as Julia Wise, a new intern.

Grey’s Anatomy: In case you worried about Callie Torres’ love life, this news might ease your mind. Arizona Robbin’s stay at Seattle Grace has just been extended to at least the end of this season. If things go well, we could even see Jessica Capshaw as a series regular next fall.

Gossip Girl: The younger version of Lily van der Woodsen has just now been given a face. According to the Hollywood Reporter, Brittany Snow (American Dreams) will play the young socialite in CW’s planned spinoff. The character will be introduced in flashback during the May 11 episode of Gossip Girl.

In other GG news, two new members of Nate’s family will be coming into the picture. Broadway star Aaron Tveit will play the teen’s wealthy cousin, Tripp Vanderbilt, while Holley Fain (Lipstick Jungle) has been cast as Tripp’s fiancee.

One Tree Hill: Later this month, Nick Lachey will get a chance to do what he does best: play himself. On April 27, Jessica Simpson’s ex will make a guest appearance on the CW program in hopes of finding his

next hit. Rumor has it, Haley may have been the one who wrote it.

Entourage: The sixth season will be starting off on a bright note for Eric. Entertainment Weekly reports that Alexis Dziena (Invasion) will be entering the scene has a new love interest for Kevin Connolly’s character. Dziena - who is slated for a recurring role - will play “a beautiful, funny, smart, grounded, self-assured, non-Hollywood-type.” Apparently a few of those still exist.

Law & Order: SVU: Carol Burnett will be leaving comedy far, far behind for her upcoming NBC appearance. In just a few weeks, the TV legend will play a former dancer with some connection to a murdered young couple. Keep a ear out for the Tarzan yell on March 17.

Private Practice: Taye Diggs’ real-life wife may soon be igniting sparks with another man. Later this season, Broadway star Idina Menzel (Rent) will guest in several episodes as the mother of one of Pete’s patients. (We can only guess what will happen next.) No air dates have yet been announced.