Having had little luck getting new drama series launched this season, ABC has decided a "Grey's Anatomy" spinoff might be in order.

The new drama would star one of the hot, horny doctors of Seattle Grace -- Kate Walsh's character, neonatal surgeon Addison Montgomery.

And Taye Diggs, who starred in ABC's short-lived "Day Break" -- you know, the "Groundhog Day"-esque drama that briefly filled the "Lost" time slot -- also has been signed to the spinoff.

As usual with spinoffs these days, it will be tried out as an episode of the mothership show -- in this case a two-hour episode centered on Addison on the brink of leaving the hospital.

Expect to see it the first or second Thursday of the May ratings sweeps if ABC plans to wait and see how it flies with viewers before deciding whether to give it a series order and put it on the fall schedule.

ABC is scheduled to unveil its 2007-08 prime-time lineup to advertisers on May 15.

The episode will serve as what is known as a "backdoor pilot" for the spinoff, which would be exec-produced by "Grey's" creator Shonda Rhimes.

"Grey's Anatomy" is on a roll this season. Moved to Thursday nights, it's holding its own against CBS juggernaut "CSI." With an average of about 20 million viewers to "CSI's" 20.7 million, "Grey's" also handily beats the CBS series among younger viewers. Heck, among college-age viewers it's even beating "American Idol" these days.

Last week, "Grey's" copped 26 million viewers -- its biggest audience ever, except when it aired right after the Super Bowl.

ABC has leaped from third place to first among younger viewers on the most competitive night of the week, nearly doubling its audience, thanks largely to "Grey's."

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In this cold, hard world in which we live, it's easy to become so cynical that when a television network promises to bring back at "some time in the future" a new drama series that sank so far in the ratings it got yanked way back in the November sweeps, a gal tends to respond by asking the network what sort of fool it takes her for.

And yet, miraculously, ABC announced late yesterday that "Six Degrees" is returning to its prime-time lineup on Friday, March 23.

Moreover, another new drama series, "October Road," will premiere on Thursday, March 15, getting the super-fab post-"Grey's Anatomy" 10 p.m. time slot.

ABC says the current occupant, "Men in Trees," will return to that slot after an initial run of the new series. And, in light of yesterday's "Six Degrees" development, by gum, we believe it.

In case you've forgot, "Six Degrees" is a serialized drama about six random people -- with nothing in common except that they are good-looking and fall into the important 18-to-49-year-old bracket so desirable to advertisers -- whose lives inexplicably start to intersect. Most important, they intersect with J.J. Abrams, who is among the show's executive producers and who has been a very big deal over at ABC.

Six episodes of "Six Degrees" aired before ABC deep-sixed it. That's because it was running in that super-fab post-"Grey's Anatomy" spot but clocking only about 9.7 million viewers, which is hard to do. You could probably air "Puppy Bowl" in the post-"Grey's Anatomy" time slot and do 9.7 million viewers.

On Fridays at 9, however, where ABC has aired this and that all season, including the aforementioned "Men in Trees" as well as newsmags, movies and the occasional rerun of "Grey's Anatomy," the network has averaged only 6.9 million viewers. "Six" need only continue to do the kind of number that got it yanked back in November to make ABC suits happy that they had made good on their promise to bring back "Six Degrees" at some future date.

There are seven episodes left on the show's original 13-episode order. Grievously, ABC has booked only four of them at this point; it's up to you 9.7 million folks out there who once saw something in "Six" to make sure we get to see the other three.

"October Road," meanwhile, is about a young, popular author guy who decides the way to get over his writer's block is to move back home, where he must face all the people he ticked off when he used their best bits in that semi-autobiographical bestseller he wrote that made him a young, popular author, and who naturally wonder if he's just stopping by to collect fresh material. That includes his ex-girlfriend Hannah, who may have had his child. You can see her point.