Zap2It has posted great summaries of the upcoming network TV seasons, including cancellations, details about each new show, and prime-time schedules.
New sci-fi, spooky, or supernatural themed shows: Invasion (ABC, Wednesdays @ 10), The Night Stalker (remake, ABC, Thursdays @ 9), Ghost Whisperer (Medium ripoff, CBS, Fridays at 8), Threshold (with Brent Spiner, CBS, Fridays @ 9), Fathom (NBC, Mondays @ 8), Supernatural (WB, Tuesdays at 9)
Has some real potential: Prison Break (FOX, Mondays @ 9)
New cop or "procedural investigation" shows: Too many to list! None look very interesting.
New sitcoms: Who cares? However, Seth Greene is part of the ensemble in Four Kings (NBC, time unknown). Jason Lee is also starring in the "quirky" My Name Is Earl (NBC, Tuesdays @ 9).
(AVSForum member Xesdeeni has put all the new schedule data into a grid.)