"So excited!! I'm going to be doing an episode of #30Rock! one of my favorite shows!!!!!" she tweeted.
James Marsden has also booked a '30 Rock' role. EW reports his role could be recurring, but NBC isn't revealing details. Could he be Liz Lemon's new lover?
Richards and Marsden join previously announced recurring guest star Will Arnett on the upcoming season of '30 Rock.' No premiere date has been given, but best guess is it'll show up on NBC sometime in the winter.
In other casting news ...
Gloria Votsis will romance Jeremy Sisto on 'Suburgatory.' Votsis will appear in the Thanksgiving episode of the new ABC comedy. [EW]
Coach Beiste is getting a love interest on 'Glee.' Eric Bruskotter will play Johnny, a football recruiter who comes to McKinley High looking for talent but falls for the coach. The role is potentially recurring. [TVLine]
Charles S. Dutton will guest star on 'Criminal Minds.' Dutton will play Tony Colt, a boxing trainer whose favorite pupil turns out to be a serial killer. [TV Guide]
Roger Bart, Edward Furlong and Tom Sizemore will guest star on 'Perception.'The trio of actors will play opposite 'Will & Grace' star Eric McCormack who stars as Dr. Daniel Pierce, an eccentric neuroscientist who helps out the FBI. [TV Guide]
'New Girl' has added a new girl. 'Party Down' Lizzy Caplan will appear in three episodes of the new hit comedy. Caplan will play Julia, a new love interest for Nick. [THR]
'Prom' star Thomas McDonell will guest star on two episodes of 'Suburgatory.' McDonnell will play Scott, a boy Tessa and Dalia both fall for. [TV Guide]