So far Rock Star: Supernova is proving a bit of a misnomer for CBS, being neither a rock star nor a supernova in the ratings.

Billed as an edgier American Idol, in which Mötley Crüe drummer Tommy Lee, former Metallica bassist Jason Newsted and ex-Guns N' Roses guitarist Gilby Clarke audition a group of wannabe rockers to front the trio's newly formed band, Supernova, the singing contest was merely solid in its debut last week--a record low-rated week dominated by reality shows, crime-show reruns and, inevitably, firework displays.

The Mark Burnett-produced Rock Star averaged 5.3 million viewers for its 90-minute premiere last Wednesday to rank 42nd in the weekly Nielsen charts, while the elimination episode on Thursday was up to 6 million viewers, good enough for 29th place.

Those numbers are in line with last summer's inaugural edition, in which INXS came out of the mothballs to tap former Elvis impersonator J.D. Fortune to take over for the late Michael Hutchence. Rock Star: INXS's weekly episodes averaged between 5.4 million and 6 million viewers.

CBS got better bang from the debut of Big Brother: All Stars. More than 7.5 million lookyloos tuned in to see such fan favorites as "Chicken George" and "Mike Boogie" again locked down in a Studio City domicile, good enough to rank 13th for the week.

But the big-time reality players remain NBC's top-ranked America's Got Talent (12 million viewers) and Fox's double dose of So You Think You Can Dance, whose Wednesday episode attracted 9.8 million viewers (number two for the week) and Thursday installment, 8.8 million (number six).

Meanwhile, NBC outdueled CBS in the pyrotechnics department, with the Peacock's Macy's July 4th Fireworks (8 million, 11th place) topping the Eyeball's Boston Pops Fireworks (7 million, 20th place).

Nevertheless, with the decent showings of its two summer reality premieres, and the continued success of its crime-show reruns (various CSIs were sprinkled through the Top 10, with support from Cold Case), CBS won the week among total viewers, averaging 6.5 million. NBC (6 million), Fox (5.1 million) and ABC (4.8 million) followed. Fox took the crown in the advertiser-friendly 18-49 demo, followed by NBC, CBS and ABC. The Big Four's average of 20.8 million in prime time last week was the lowest on record.

ABC's lone bright spot was Grey's Anatomy. Milking the show's 11 Emmy nods, ABC rebroadcast three episodes last week, all placing in the Top 25. On the flip side, Master of Champions, the network's attempt to duplicate last year's surprise summer run of Dancing with the Stars, is mastering mediocrity, averaging 5.2 million viewers in 44th place.

Of course, the Alphabet number-crunching department preferred to see the bottom-dwelling glass as half-full. "The Fourth of July holiday [is] traditionally the week with the lowest TV usage levels of the year," the network said in its weekly ratings release. "ABC was the only broadcaster to grow its adult 18-49 audience week-to-week." Yippee.

Finally, USA's Psych premiered with 6.1 million viewers, the highest-rated new scripted series on basic cable this year.

Here's a rundown of the most watched shows for the week ended Sunday, per Nielsen Media Research:

1. America's Got Talent, NBC, 12 million viewers
2. So You Think You Can Dance (Wednesday), Fox, 9.8 million viewers
3. CSI, CBS, 9.7 million viewers
4. 60 Minutes, CBS, 9.1 million viewers
5. Law & Order: Criminal Intent, NBC, 8.9 million viewers
6. So You Think You Can Dance (Thursday), Fox, 8.84 million viewers
7. Cold Case, CBS, 8.82 million viewers
8. CSI: Miami (Thursday), CBS, 8.7 million viewers
9. CSI: Miami (Monday), CBS, 8.2 million viewers
10. Law & Order, NBC, 8.16 million viewers