Stay tuned for live coverage from 1200.
1201: And here we go. Brown starts with condolences for fallen troops, and also for the late Labour MP Ashok Kumar and his family. For the first question, Tony Baldry takes on Brown over his claim that defence expendintue has risen in real terms under Labour. A note from the House of Commons library has since shown this to be "incorrect". Brown says that he is already writing to Chilcot to correct this. Brown: "I do accept that, in one or two years, defence expenditure did not rise in real terms" - but it did rise in cash terms. Not a good start for the PM.
1205: Cameron now. After condolences, he leads by sarcastically thanking Brown for his answer to Tony Baldry. Cameron exclaims that he's never before heard Brown apologise for or retract one of his misleading claims before.
1207: Unsuprisingly, Cameron's first question is about the trouble at BA. Brown's response is to paint this as Tory politicking. He says that he would have hoped for "cross-party support" in finding a resolution. Plenty of sanctimoniousness about "looking out for ordinary families."
1208: Cameron rightly says that Brown's response was "weak". He adds that "it's like a return to the 1970s". His question: "Will you join me in urging Unite members to cross the picket line?"
1210: Brown's dodging a response. One of his "answers" makes a mockery of this entire exercise - he simply reads a Telegraph story from last year, saying that the Tories are meeting with the unions. The Speaker should intervene, I think. But he doesn't.
1212: Cameron keeps asking the same question - and Brown keeps responding with claims that the Tories are being "partisan" and that he wants a "resolution" to the situation. It's grim stuff, but it's holding off the killing blow, so far.
1213: Cameron turns up the heat, saying that Labour are "a wholly-owned subsidiary of the Unite union". Brown gets in his prepared gag: "No wonder he uses no notes - he's got nothing to say."
1215: It's Nick Clegg now, and he leads off by claiming that "Charlie Whelan and Lord Ashcroft are exactly the same". The backbenches roar, and there are plenty of shout of "Michael Brown".
1215: Brown's response is to say that Labour have tried to reform party funding - but the Tories "blocked" that. Hm. He aslo gets in a dig at Ashcroft.
1221: Questions about the Budget, regional development and Dover port. John Redwood asks Brown about RBS loans.
1224: Brown claims that unemployment "would rise" under the Tories.
1232: Gerald Howarth highlights Charlie Whelan's role as one of the "forces of Hell" - and asks, simply, why he is involved with the Downing St operation. Brown gets all self-righteous again - saying that the Tories are trying to turn an "industrial action into a political football." Weird, that, because I didn't hear mention of BA. Brown then adds that the Tories "should be ashamed of themselves". So, shameless stuff from Brown, then.
1232: And that's it. Verdict shortly.
VERDICT: To my eyes, that was one of those PMQs where Cameron didn't really land a killing blow on Brown – but didn't actually need to in order to emerge triumphant. The main story coming out of it will be how Brown repeatedly dodged the question over whether he would encourage Unite members to cross the picket lines – which, given the increased airplay that Brown's links with Charlie Whelan are getting, isn't going to play well for the PM. Throw in Brown's embarrassment over those defence spending figures, and it starts looking even worse for him. One to cheer Tory hearts, even if I feel they need to move on from Unite fairly soon.