What we're watching: The NCAA Tournament marches on, but we're most interested to Six Degrees see back on ABC.

Our traditional high definition listings continue below.

Here are some other HDTV programs showing on selected networks today. All times are Eastern reruns are in italics, premieres in bold:

ABC (720p): Grey's Anatomy (8 p.m.), Six Degrees (9 p.m.)

CBS (1080i): NCAA Basketball Championship Regional Semifinal (7 p.m.)

NBC (1080i): The Tonight Show with Jay Leno (11:34 p.m.)

Fox (720p): House (8 p.m.)

CW (1080i): N/A

MYNTV (1080i): N/A

Discovery-HD (1080i): Panda Nursery (7 p.m.), The Desert Speaks (8 & 11 p.m.), White Hot Winter (8:30 p.m.), Yellowstone: America's First National Park (9 p.m.), Fantastic Festivals of the World (10 p.m.)

TNT-HD (1080i): Law & Order (6 & 7 p.m.), A Time to Kill (8 p.m.), Along Came a Spider (11 p.m.)

ESPN-HD (720p): SportsCenter (11 p.m.)

ESPN2-HD (720p): Friday Night Fights: Rodriguez vs. Feliciano (9 p.m.)

INHD (1080i): London Live (7 & 7:30 p.m.), NBA TV: Lakers at Hornets (8 p.m.)

Universal HD (1080i): Law & Order: SVU (7 p.m.), Firefly (8 p.m.), Surface (9 p.m.), Ghostbusters II (10 p.m.)

HDNet (1080i): Arrested Development (7 & 7:30 p.m.),Geek to Freak with Dennis Rodman (8 & 11 p.m.), Deadline! (8:30 & 11:30 p.m.), Art Mann Presents... (9 p.m.), Mixed Martial Arts (9:30 p.m.)

HDNet Movies (1080i): Color Me Kubrick: A True...ish Story (8 & 11:05 p.m.), Who is Cletis Tout? (9:30 p.m.)

HBO-HD (1080i): Doctor Dolittle (6:30 p.m.), Rome (8, 9 & 10 p.m.)

MAX-HD (1080i): V for Vendetta (6 p.m.), ATL (8:15 p.m.), Jarhead (10 p.m.)

STZ HD (1080i): Silent Hill (9 p.m.), Flightplan (11:10 p.m.)

Showtime (1080i): Into the Blue (6 p.m.), This American Life: Reality Check (8 & 8:30 p.m.), The L Word (9 p.m.), Debbie Does Dallas Again (11 & 11:30 p.m.)

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