A few weeks in to the new US TV season now and we're beginning to get a clearer picture of how the various new and returning series are stacking up in the ratings. In the coming days Tube Talk will be taking a closer look at exactly how well our favourite US shows are performing. (Brace yourselves, because in some cases it's not pretty reading).

Terminator: The Sarah Connor Chronicles (FOX)
Hopes were high for this high-action drama after the nine-episode first season impressed at midseason, with an average of 11.4 million viewers. The second season has struggled in the more competitive Fall lineup, premiering on September 8 with just 6.34 million and averaging around 5.5 million since. The show is now expected to be axed within months, if not weeks.

Prison Break (FOX)
The dismal performance of Sarah Connor has been partly to blame for the equally disappointing ratings for Prison Break, which airs straight after the Terminator spinoff on Monday nights. Season four began on September 1 with 6.48 million viewers and has since dropped off to around 5.4 million. To put those numbers into context: season one averaged 12.1 million, season two had 10.1 million and the much-derided third season managed 8.2 million. The show still performs well in the coveted 18-49 demographic and the network is a fan - plans for a spinoff are still in the works - so it is likely to stick around for the foreseeable.

Chuck (NBC)
It's only two episodes in to its second season, so it might be a little early to call the fate of comedy spy drama Chuck, but the initial signs aren't especially positive. The premiere pulled in 6.62 million viewers on September 29, a lower audience than any episode of the 13-episode first season. This week it dropped off to 5.89 million. Like Prison Break though, the 18-49 numbers are strong so NBC will be content for now. In fact, the network has already ordered a full season of 22 episodes.

Gossip Girl (The CW)
Finally, a success story! Teen drama Gossip Girl returned last month to its best ever numbers. The premiere managed 3.38 million on September 1 and the audience went on to grow to a series best of 3.73 million on September 15. The most recent episode delivered a very healthy 3.54 million on September 29. Background: the first season averaged 2.61 million, with only one episode managing more than 3 million (the premiere, with 3.65 million).

Heroes (NBC)
Despite pulling off what has been almost universally regarded as a triumphant creative renewal, Heroes has returned to some of its lowest numbers ever. The third season premiered on September 22 with 10.22 million viewers, down on the 14.3 million who watched the series premiere in 2006 and the 14.12 million who watched the start of season two. On September 29 the audience fell to 9.34 million and this week it fell further to an alarmingly low 8.21 million. Prior to season three, only one episode had pulled in fewer than 10 million viewers (ironically, the season two episode in which the pace picked up). The good news? Heroes has 50% more viewers in the 18-49 demo than an average NBC show, so it's a safe bet that Milo and co. will be around to protect us from the villains of this world for a good while yet.

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