"If it's true," the only three words you need to care about before reading further, but according to gossip site Kotaku, GameSpot's executive editor Jeff Gerstmann was pink-slipped at some point in the last 24-48 hours, with the scuttlebutt fingering his 6.0 score of Eidos's Kane & Lynch.
Kane & Lynch is an action game about a "flawed" mercenary and a medicated psychopath on a "violent and chaotic arc of redemption and revenge," i.e. "shooter spree" for the PC, PlayStation 3, and Xbox 360. I mentioned it back in October after WomenGamers.com took umbrage with -- I had to agree -- a pretty disappointingly gender-exploitive ad campaign that preceded the game's debut. Other than that, I haven't played the game.
Gerstmann's 6.0 carried a "fair" tag on GameSpot's scale, i.e. slightly above average, and reasonably well north of "bad."

Kotaku's running this pic on its site, showing the quite prominent Kane & Lynch "skin" GameSpot was running as part of its K&L advertisement deal
According to Shacknews in this posting, which cites "reports" (but to be fair, doesn't source them) Eidos reacted to the review by threatening to pull a substantial ad contract. Shacknews says it "can confidently confirm via its own sources that Gerstmann was indeed fired yesterday from his position at GameSpot." Note that's a claim that the firing happened, not the reasons for it.
Anyway, I don't know Gerstmann personally, and as a rule, I don't read GameSpot for its reviews, but regardless, his firing deserves critical examination, especially with ugly rumors like these circulating. Hey, it's even possible the anonymous rumormongers are just Gerstmann supporters sowing the seeds of discontent. In a he-said, she-said, you can never be too skeptical.
But if the sponsors were directly or indirectly "manufacturing consent" via payola...again, don't assume that's true, but if it somehow turns out to be, keep your pitchforks handy.
UPDATE (11/30 11:59 a.m. CST): Just spotted this Joystiq post which notes that:
Jeff has confirmed his firing to us via e-mail, but says he's "not really able to comment on the specifics of my termination." He added that he's "looking forward to getting back out there and figuring out what's next."
UPDATE (11/30 1:18 p.m. CST): Here's Gerstmann's GameSpot video review of Kane & Lynch, which has been pulled from GameSpot's website, and which some are speculating may have had something to do with Gerstmann's termination.
My take: First, Gerstmann's tone, while entirely relaxed and not really rancorous, doesn't match his 6.0 "fair" (from the video review, it sure doesn't sound like an "above average" game to me).
Second, he occasionally rambles in a way that might confuse or lose casual readers. I'm thinking the part where he's dismissing the game's story ("because they [the in-game criminal organization] think that he [Kane] screwed them over and all this other stuff") and a bit later when he's trying to describe the cover mechanic (but doesn't, really, if you listen carefully) as well as the dismissal of the A.I. with "they get stuck on cars and run in circles and do all kinds of dumb stuff."
I can sympathize with Gerstmann's disdain, since he's referring to tired game design cliches that therefore have a tendency to sound like game review cliches, but you still have to spell things out clearly (no sloppy summarizing) which in this case would've worked by simply sticking with specific points and excising abstract, dismissive phrases like "all kinds of dumb stuff."
UPDATE (11/30 6:26 p.m. CST): Joystiq contacted Eidos PR and passed along the following from Cnet representative Sarah Cain.
While reiterating that CNET does not discuss personal employee matters with the press, Cain said directly that "we do not terminate employees based on external pressure from advertisers." When asked specifically about whether any such pressure was even attempted on Eidos' part, Cain had no comment.