Channel Surfing: "90210," Ashley Jensen, Trailer for "Merlin" Unveiled, NBC Shakeup, and More

Good morning and welcome to your Tuesday morning television briefing. Like many of you out there, I'm bummed that my three-day weekend sailed by far too quickly... but am also thrilled that the fall TV season is finally upon us.

Digital Spy has a roughly 90-second trailer up for Merlin, which airs on BBC One and on NBC this winter and stars Colin Morgan, Anthony Stewart Head, Michelle Ryan, Richard Wilson, Katie McGrath, Bradley James, Angel Coulby, and Santiago Cabrera. (Digital Spy)

90210 mania is upon us with mere hours to go before the launch of 90210 2.0, as it were. EW.com has some behind-the-scenes footage and interviews with Jennie Garth and Shannen Doherty from their recent cover shoot. (Entertainment Weekly's PopWatch)

Shannen Doherty, meanwhile, sat down with the Los Angeles Times for a brief interview, in which she said that the sudden goodwill being directed towards her from the public "definitely feels good" and "also feels scary." (Los Angeles Times)

While most Americans know her best from her turn as Christina on Ugly Betty, Ashley Jensen won me over much earlier with her winning performance as Maggie Jacobs on HBO/BBC's Extras. She's up for an Emmy in the supporting actress (mini-series or movie) category and talks about the nomination, Extras, and what happens to Christina on Ugly Betty. (USA Today)

Nikki Finke claims that NBC wants to fire second-in-command Teri Weinberg and "hopes that Ben Silverman quits very soon." She says that Marc Graboff and Katherine Pope will take up the reins at the network. Silverman's contract is up in December, but he's said to be looking to secure a way out before then. (Deadline Hollywood Daily)

PBS has launched 40 half-hour episodes of kids program Sid the Science Kid from Henson's Creature Shop, which will produce the series via its new Digital Puppetry Studio, which uses a puppet motion-capture technology and applies it to CGI-derived characters and environments. (Hollywood Reporter)

MTV is launching a global HD service on September 15th. (Variety)

Stay tuned.