Reliable hits like “Dancing With the Stars,” “Grey’s Anatomy” and “Desperate Housewives” helped ABC to once again kick off the season as the top-rated primetime network, but CBS also could cheer, as some of its vets returned especially strong and it claimed premiere week’s top new show.

There certainly was reason for the broadcasters to be nervous about fall, but so far they’ve held their own. Coming off a disastrous strike-impacted season, the mood around town has been one of cautious optimism — even if no new series is a breakout smash.

Nielsen estimates that the five broadcast nets dipped by 3% in adults 18-49 vs. their year-ago premiere week (14.5 vs. 15.0) — not bad considering that Nielsen’s sample of homes with DVRs has jumped from 20% last year to 28% for the first week of this season.

Also, unlike last year when the top new skeins bowed during premiere week, three of this season’s biggest hopes — CBS’ “Eleventh Hour,” ABC’s “Life on Mars” and NBC’s “My Own Worst Enemy” — have yet to launch. Ditto for the season preem of the Eye’s top show, “CSI.”

The broadcast nets will see viewership figures spike when all seven-day DVR playback totals are tabulated, but that’s not necessarily a good thing, as they haven’t devised a way to monetize such delayed viewing.

Looking at the Sept. 22-28 frame, ABC vets “Grey’s Anatomy” (7.4 rating/18 share in adults 18-49, 18.47 million viewers overall) and “Desperate Housewives” (7.1/16, 18.68m) topped the 18-49 rankings in lifting the Alphabet to its fourth straight premiere week victory in the closely watched demo.

ABC’s 3.8 rating/10 share in 18-49 repped a 3% decline vs. last year, and comfortably topped NBC (3.3/9), CBS (3.1/8) and Fox (3.0/8). Univision ran fourth (1.5/4) and CW placed fifth (1.3/3).

Fox (boosted by Sunday football) and CW were both up vs. the same frame a year ago while NBC saw the biggest declines (15%, in part due to a special ratings rule related to “Heroes” that boosted its year-ago averages in premiere week).

The Alphabet also prevailed in adults 25-54 (4.5/11 to a 4.1/10 for runner-up CBS) as well as total viewers (12.26 million to 11.23 million), marking the first time since the mid-’90s that ABC has finished on top in total viewers during premiere week in two consecutive years.

“Dancing With the Stars” played a key role as usual for ABC, with Monday’s premiere (5.3/13 in 18-49, 21.34m) ranking fourth in 18-49 and first in total viewers. The net aired five hours of the show, including another two-hour performance seg on Tuesday (4.7/12, 18.30m) and Wednesday’s results show (3.6/10, 15.87m).

ABC didn’t do much Tuesday with its only series premiere of the week, the traveling gameshow “Opportunity Knocks” (1.8/5, 6.56m), which ran fourth in its tough 8 p.m. hour.

NBC finished second for the week in 18-49 thanks to its NFL “Sunday Night Football” matchup between Philadelphia and Chicago (6.9/17, 17.34m), which was up more than 10% vs. the same week a year ago.

The net welcomed “Heroes” back with a two-hour seg (5.0/12 in 18-49, 10.09m) and was also repped in the top 10 by “The Office” (4.9/12, 9.34m), which approached its series high despite a weaker lead-in from “My Name Is Earl” (2.7/8, 6.40m).

NBC’s Sunday premieres of “Knight Rider” (2.5/7 in 18-49, 7.35m) and “Lipstick Jungle” (2.4/6, 6.25m) were less impressive, although the latter led its timeslot among upscale 18-49ers.

Net noted that its median age for premiere week was a spry 43.9 years, putting it closer to Fox (42.7) than either ABC (50.5) or CBS (53.5).

CBS was paced by Monday’s “Two and a Half Men” (5.3/12 in 18-49, 14.88m) and “CSI: Miami” (5.2/13, 17.23m), which were both up vs. their year-ago bows — as was skedmate “How I Met Your Mother” (4.0/10, 9.79m), which had its best launch yet.

One of the week’s most impressive perfs came Tuesday from the net’s fifth-season bow of “NCIS” (3.6/10 in 18-49, 18.03m), which had its best-ever preem in both 25-54 and total viewers. In 25-54, “NCIS” finished within 1 share of Fox’s “House.”

And behind “NCIS,” new Simon Baker drama “The Mentalist” looked good (3.5/9, 15.60m), collecting the week’s best premiere numbers.

Frosh Wednesday comedy “Gary Unmarried” (2.4/7 in 18-49, 6.82m) looked OK relative to its weak lead-in, and lead-out “Criminal Minds” had a strong preem (4.7/12, 17.01m), rising nicely year to year. And on Thursday, “Survivor” remained solid in its two-hour preem (4.5/11, 13.06m) despite seeing more year-to-year erosion.

Fox was paced by its winning Tuesday lineup of “House” (5.1/14, 12.38m) and rookie “Fringe” (4.1/10, 9.42m), which was returned to earth after its week-earlier surge.

Also solid but unspectacular for the net were Wednesday’s “Bones” (3.1/9, 9.73m) and Sunday’s season preems of “The Simpsons” (4.5/12, 9.47m) and “Family Guy” (4.5/10, 9.09m).

CW’s growth was sparked by solid numbers across the week, including Monday’s “Gossip Girl” and “One Tree Hill,” Tuesday’s “90210,” Wednesday’s “America’s Next Top Model” and Thursday’s “Smallville.” Week also marked the final seg of “Friday Night Smackdown” (1.4/4, 4.41m) as the franchise shifts to MyNetwork beginning this week.

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Of note on Monday of the current week, NBC’s “Chuck” returned to nothing-special numbers and Fox’s dramas dropped while CW’s grew.

“Chuck” (2.7/7 in 18-49, 6.84m), off since January, fell sharply from its series preem, and lead-out “Heroes” (4.5/11, 9.50m) was on the low side in its second week but scored a narrow 18-49 victory for its hour. Both seem to have lost momentum after being sidelined by the writers strike.

“Chuck” did beat out Fox’s “Terminator: The Sarah Connor Chronicles” (2.0/5, 5.37m), as the latter soph skein continues to struggle opening the night. And vet lead-out “Prison Break” (2.1/5, 5.28m) kept the net in fourth place among the broadcasters.

Both Fox hours barely held on in 18-49 against CW’s “Gossip Girl” (1.8/5, 3.40m) and “One Tree Hill” (1.9/4, 3.42m), with “Girl” and “Hill” easily topping their Fox rivals in 18-34.

“One Tree Hill,” now in its sixth season, built a bit on its “Gossip Girl” lead-in (2.7/7 vs. 2.6/8 in 18-34), matching its best CW score to date. Combined they gave CW its highest-rated in-season Monday in the demo, and it stood as the night’s top net in women 18-34 (3.9/10).

CBS won in 18-49 behind “Two and a Half Men” (4.7/11 in 18-49, 13.58m) and “CSI: Miami” (4.4/11, 14.34m). Though both were down week to week, the new show airing between them, “Worst Week” (2.9/7, 8.96m), dropped a more alarming 24% and retained just 62% of its “Men” lead-in (vs. 72% in premiere week.)

Next week could be key for “Worst Week” as it opposes ABC’s returning laffer “Samantha Who?” which takes over at 9:30 as “Dancing With the Stars” reverts to its normal 90 minutes.

ABC was paced by “Dancing” (4.4/11, 18.88m), which won its timeslot but saw a sharper than usual decline from its premiere to week two.