Risk, politics, and GDP
Predictably, politicians on both sides of the argument over the economy have taken today's figures as support for their view.
For Chancellor Osborne, the strength of the recovery shows he was right to start cutting the deficit faster, and sooner. But naturally Alistair Darling says it shows he was right to support the economy when he did - and that Mr Osborne's plans are putting the recovery at risk.
Surprise surprise, I don't think this one set of figures decides the issue either way.
Mr Darling is right to point out that government spending played an important role in today's growth figure. The coming slowdown in government spending - consumption and investment - is another big reason to doubt that growth at this pace will be sustained. But there's little in today's numbers to suggest that Mr Osborne is about to tip us back into recession.
As we've seen, the lion's share of the extra output in those three months was due to the services sector, and construction. Both were given ample support by the government. The ONS data show that government services accounted for more than 20% of the extra growth.
We also know that public building projects will have played an important role in the jump in construction output - though quite how much of a role is difficult to judge because the lead-times for construction are so long.
New public construction orders recently overtook private ones - for the first time since the 1970s.
Some of those will be housing projects that would come on fairly quickly - so orders from the first quarter of this year could well be showing up in the output data we got today.
But when it comes to schools and hospitals projects, industry experts tell me that it would be new orders from 2009 that would be showing up in the second quarter data. Public non-housing construction orders for schools and hospitals grew by 10% in 2009, while infrastructure orders were up by 44% over the previous year.
So Mr Darling is right to say that he laid some of the foundations for this growth when he decided back in 2008 to bring forward capital spending into 2008/09 and 2009/10.
But the same industry insiders also tell me that long lead-times can't entirely account for the burst in public construction activity in the second quarter. They claim there was also a burst of public sector activity in the lead-up to the election.
If so, that would suggest that the talk of slash and burn contracting and pre-election sweeteners by the outgoing government has some basis in the facts, and helped push up the output numbers we saw today.
Whatever the truth behind the construction rise, it's safe to say that the public component will fall back sharply over the next year - though, given the lead-times, it's unlikely to happen all at once.
But today's figures show strength in other parts of the economy as well - the most encouraging thing about them is that the growth is fairly broad-based, even if the headline number is skewed by that jump in construction. Manufacturing grew by 1.6%. That's the third quarter in a row where growth has topped 1%.
The city commentators are probably right that this will be as "good as it gets" for the UK economy - at least for a while. But that's a phrase that many had prepared in advance - in the expectation of a much weaker set of numbers.
It's right to be cautious. If an annualised growth rate of well over 4% is as good as it gets in this recovery, we could still be getting it pretty good.