I think his most profound statement is "that there has been no statically significant global warming in the last 15 years"

Statically significant is a very low standard. Science won’t even fund a project unless it meets this threshold.

Basically, he just admitted that this so-called "Global Warming" thing is all a hoax.
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The emails indicate that they weren’t being honest about the data. They were acting as political activists. Mann started the business of revising the climate record by cherry picking data and flat out fraud as was demonstrated by his adding adjusted modern thermometer record to his tree ring data because the two didn’t match. It also demonstrated how the smoothed the data. Much of the emails were instructive in that they showed how they were not able to find evidence for their agenda. They acted in an unscientific manner by stacking the deck so that only a small closed group of people were allowed to do peer review and the attacked people and publications that didn’t buy what they knew was contrived data. It showed them acting as leftist activists and not scientists. They even managed to discredit the raw data they used. There is zero integrity in Mann. That guy lies when the truth makes a better story. Jones seems to believe in his fairytale but judges other peoples worth by how left wing they are. He is clearly not acting as a scientists but as someone pushing an agenda.

It doesn’t really change the state of the evidence. It was completely obvious that Mann lied and invented the Hockey stick for political reasons. Now with those lies illustrated by their own words, it is obvious to anyone, not just people who had some knowledge of climate history.
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The significance is that deniers can take the correspondence out of context and intentionally misinterpret it to try and confuse the public about the evidence for global warming, which is huge. As for the scientific significance, there is virtually none. Even if you ignore that data the evidence for AGW is overwhelming.

EDIT: Don’t be intentionally stupid Eric, the emails are not going to change the laws of radiative transfer, or that CO2 is a greenhouse gas, or that the models predict warming, or that temperatures have been rising, or that changes in phenology are seen around the world, or that glaciers have been retreating, and that there’s less arctic ice, etc. Also, under peer review you wouldn’t have people whose work is proxy reconstruction reviewing papers of people whose work is satellite temperatures, or model output, etc. People review work in fields similar to their own–that’s the point, they’re peers. The evidence for warming comes from so many different fields that the scope of papers that Jones, Mann, etc. would review would not begin to cover it.
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It is of the utmost significance when the leader Prof. Phil Jones says, "that there has been no statically significant global warming in the last 15 years" All the time whilst they were telling us we had to act now due to dangerous man made global warming that was going to destroy the world!

How Dana and the other activists can dismiss this fact really tells you a lot about their integrity!
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You provide an excellent example with your follow-on to the question. There is nothing in the stolen e-mails that shows the "hockey stick" data to be wrong, and that particular dataset is independent of hundreds of other lines of inquiry showing global warming to be a real problem, to say nothing of the irrefutable physics behind the phenomena producing the datasets.

None the less, the stolen e-mails, by logic akin to "have you stopped beating your wife, yes or no?" have provided fuel to keep the massive denier propaganda effort alive and well.
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