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

iCarly: American Idol finalist David Archuleta will be targeting the teen demos when he makes a stop on Nickelodeon. In the appearance, which will be taped this Thursday, the singer will play…himself. But there will be a twist. Instead of being known for his FOX show, Archuleta will be a contestant on a program called “America Sings.” This guest stint not-so-coincidentally comes around the time David’s first album drops. His self-titled debut hits stores on November 11.)

Eli Stone: Katie Holmes has now made it hip for Dawson’s Creek vets to visit Eli Stone. Kerr Smith, who played Jack McPhee on the WB show, will take his turn on the ABC program as one of Martin Posner’s lawyers. No word whether yet he’ll be doing his own cabaret number.

Worst Week: Although the freshman series is still relatively….fresh, it’s already managed to line up several appealing cameos. Fred Willard will be seen in two episodes later this fall as Sam’s father. I’m sure he’ll somehow add some spice to the dreaded meeting of the in-laws. Meanwhile, Olympia Dukakis (Steel Magnolias) will guest as Melanie’s grandmother. The Academy Award-winner will give the engaged couple family wedding rings which Sam, of course, then loses.

Brothers & Sisters: Jason Ritter - who can next be seen as Jeb Bush in Oliver Stone’s W. - may soon be the latest voice in the Walker family. According to E!, the actor has been in discussions to play Ryan, the clan’s half-brother. The initial air date for this new character has not been announced.

Greek: When Greek returns next spring, the Kappa Taus and Omega Chis will both be aiming to recruit Jesse McCartney. The singer/actor (can anyone name a song he sings?) will play Andy, a sought after pledge who just happens to be a friend of Calvin’s. Fortunately for pop lovers, McCartney’s role will be a recurring one.

How I Met Your Mother: This week, HIMYM just had an appearance from a burger-lovin Regis Philbin. Now the comedy is prepping to welcome another daytime star. In an upcoming episode, Eric Braeden (Victor Newman on The Young and the Restless) will guest as Robin Charles Scherbatsky, Sr. In case you haven’t figured it out—Robin would be his junior.

Grey’s Anatomy: We didn’t really think that Callie and Eric would actually remain happy, did we? According to Entertainment Weekly, Melissa George (Alias’ Lauren Reed) may be checking in as an intern who likes to keep her options open sexually. Unfortunately for McSteamy, I don’t think those options include him.