It’s the proverbial Dickensian best/worst of times at ABC these days: Its hits (“Lost,� “Grey’s Anatomy,� “Desperate Housewives� are positively powerful; most of the rest of the schedule, pretty puny. (If the network hadn’t renewed the low-rated “What About Brian,� it would’ve gone 0-for-2005 in scripted series.) So ABC Entertainment president Stephen McPherson took a huge gamble and will launch 10 new scripted series between tonight and November.

The fun, relatively speaking, begins tonight with “Men in Trees,� which stars Anne Heche as a self-help relationship guru who realizes she actually understands very little about men – only after she discovers her fiancé’s infidelity. (The show moves to its regular timeslot on Friday.) It’s seeking the quirky charm of “Northern Exposure.� I’m not persuaded it fully finds it.

But ABC has a lot of new guns in its fall arsenal. Critics so far seem to be most seduced by “Ugly Betty� – starring the winning America Ferrara in what looks like a deft “Devil Wears Prada� ripoff but is, in fact, the sixth or so remake of a famous telenovela – executive-produced by Salma Hayek, who’ll appear occasionally in hilarious glimpses of Betty’s own favorite and way-over-the-top telenovela. Tough timeslot, however: Thursdays at 8 p.m.

ABC has likewise made a bold, perhaps even foolhardy, move in devoting so much of its airtime to strenuously serialized fare, such as “The Nine,� “Day Break,� “Six Degrees� and even most of its new sitcoms. Its current hits cited above are all serials, and every one of the new shows that connect will be considered appointment television. Those that fail, however, could kill their timeslots for the season.

Of them, the best seems to be “The Nine,� about strangers who establish a symbiotic link with one another after surviving a 52-hour hostage crisis after a botched bank heist. (Too bad they didn’t have the kids from Fox’s “Standoff� manning the negotiations; they seem to knock off two similar situations an episode, while the particulars of this one will take the entire season to fully suss out). Its characters are all intriguing; it’s appropriately moody. The one caveat is that all the characters already know what happened, and the writers will only allow this information out in dribs and drabs over the course of the season, which is kind of a storytelling cheat when it comes to a TV series. It helps that “The Nine� follows “Lost� on Wednesdays, though that didn’t sufficiently help “Invasion� last season.

“Day Break� – which will take “Lost’s timeslot in November and run straight through for its initial order of 13 seasons – is a even trickier proposition, though if executed properly could result in a really cool show. It’s been glibly dubbed “The Fugitive� meets “Groundhog Day:� Taye Diggs stars as a cop framed for murder; every morning, he wakes up to find himself stuck in the same day, though armed with the information from previous days, allowing him to alter his routine with each passing day and, presumably, solve the crime. What’s problematic is that viewers may have to pay such close attention to the show to figure out what Diggs is up to that casual viewers may throw up their hands in exasperation. With so many new shows demanding so much of viewers’ discerning (as opposed to distracted) attentions, how much can we reasonably allot to each program?

“Six Degrees� is a special pup, perhaps as un-high-concept as network TV gets. (Of all the 30 or so new shows unveiled at May’s upfront presentations, it was the only one that, after viewing its cut-down, I had absolutely no idea what it was about.) It charts the experiences of six strangers, and how they interconnect in unexpected fashions, ways the characters themselves don’t even realize. On a purely commercial level, it simply appears to be a concept too ethereal to play well to the sort of mass audience a network needs to lure (except, perhaps, ABC at 10 p.m. Thursday). But I also just sort of found it kind of incorrigibly self-satisfied with its own brand of ersatz mysticism, or, to be more blunt, just kind of unnecessarily pretentious. In my above-linked story on the proliferation of serialized dramas, series co-creator Stuart Zicherman says, “We’ve created what we like to call six shows.� Well, six shows that clearly weren’t strong enough to stand on their own; we’ll see if super-gluing them all together results in something more trenchant.

But the new ABC show I really disliked was “Brothers & Sisters,� which, despite an impressive cast (Sally Field, Rachel Griffiths, Calista Flockhart, Ron Rifkind, etc.), felt like a stab at an HBO drama, only written by robots. And robots that routinely and irritatingly freeze up on buggy Microsoft software (is that a redundancy?), and need frequent rebooting.

In the recent past, ABC’s sitcoms have been lamentable in so many ways. This season, except for “Notes from the Underbelly,� highlighting a crushingly bland principal couple, I kind of liked them (in some cases, to be fair, I was in the distinct minority). “Big Day� is a “24� parody, set against the far-less-high-stakes background of a wedding day; its characters, however, consider the stakes just as desperate as any crisis situation Jack Bauer lands himself in. “Knights of Prosperity� focuses on some doofuses (doofi?) on a quixotic quest to break into Mick Jagger’s Manhattan condo and roll off with his treasures. “Help Me Help You� follows obliquely in the tradition of “Frasier� and “The Bob Newhart Show,� upping the ante a smidge by making its resident shrink (Ted Danson) at least as lunatic as his patients.

Hence, this year, ABC trots out the most adventurous slate of new shows of any network (too frequently in the past, they offered the safest new shows), programs that will clearly divide viewers. If three of these shows do well enough to merit renewal, McPherson no doubt would be thrilled. Mark Costello’s recent novel was titled: “Big If.� Regardless, next season, McPherson would be well advised to offer viewers a lot fewer time-commitment-heavy series.