Well, this is going to be interesting. (Photo: AP Photo/M. Spencer Green)

1. Both Democrats and conservatives are going to get the exact debate they wanted. I'm not so sure about Republicans.

2. This is an admission of fear from the Romney campaign. You don't make a risky pick like Paul Ryan if you think the fundamentals favor your candidate. You make a risky pick like Paul Ryan if you think the fundamentals don't favor your candidate. And, right now, the numbers don't look good for Romney: Obama leads in the Real Clear Politics average of polls by more than four percentage points -- his largest lead since April.

3. Related point: Two of the top contenders in the Romney campaign's veepstakes were Ohio's Rob Portman and Florida's Marco Rubio. Given that there's fairly good evidence that vice presidential candidates are worth at least a point or two in their home states, the Romney campaign's decision to pick Ryan is evidence that they feel they need to change the national dynamic, not just pick off a battleground state.

4. Romney's original intention was to make the 2012 election a referendum on President Obama's management of the economy. Ryan makes it a choice between two competing plans for deficit reduction. This election increasingly resembles the Obama campaign's strategy rather than the Romney campaign's strategy.

5. It's worth recalling how Ryan became a semi-household name. It wasn't a Republican strategy to put him forward. As Ryan Lizza recounts in his New Yorker profile of Ryan, it was a Democratic strategy to put Ryan forward. Ryan, he writes, "was caught between the demands of the Republican leaders, who wanted nothing to do with his Roadmap, and his own belief that the Party had to offer a sweeping alternative vision to Obama’s. Ryan soon had an unlikely ally, in Obama himself." While Republicans were trying to keep Ryan quiet, the Obama administration was trying to make him famous. They saw his plans as the clearest distillation of the GOP's governing philosophy -- and they thought it would drive voters towards the Democrats. We'll know in November whether that was a genius strategy or an epic miscalculation.

6. Consider the case for Romney until today: He's a relatively moderate businessman running because his experience in the private-sector gives him crucial insight into how to manage the economy. Now consider Ryan: He's worked in politics his entire life, beginning as an aide to Sen. Bob Kasten, then working for Sen. Sam Brownback and as a speechwriter to Rep. Jack Kemp. He's known as a relatively ideological politician who has put forward a detailed policy plan to remake the federal government. It's a rather different message about what's important. And how does Romney say the problem with Barack Obama is that he's "never spent a day in the private sector" and then put Ryan a heartbeat away from the presidency?

7. Ryan upends Romney's whole strategy. Until now, Romney's play has been very simple: Don't get specific. In picking Ryan, he has yoked himself to each and every one of Ryan's specifics. And some of those specifics are quite...surprising. For instance: Ryan has told the Congressional Budget Office that his budget will bring all federal spending outside Medicare, Medicaid and Social Security to 3.75 percent of GDP by 2050. That means defense, infrastructure, education, food safety, basic research, and food stamps -- to name just a few -- will be less than four percent of GDP in 2050. To get a sense for how unrealistic that is, Congress has never permitted defense spending to fall below three percent of GDP, and Romney has pledged that he'll never let defense spending fall beneath four percent of GDP. It will be interesting to hear him explain away the difference.

8. It's not just that Romney now has to defend Ryan's budget. To some degree, that was always going to be true. What he will now have to defend is everything else Ryan has proposed. Ryan was, for instance, the key House backer of Social Security privatization. His bill, The Social Security Personal Savings Guarantee and Prosperity Act of 2005, was so aggressive that it was rejected by the Bush administration. Now it's Romney's bill to defend. In Florida.

9. Joe Biden has a lot of debate prep ahead of him. I've interviewed Ryan three times. Twice on health care (here and here), and once on economics (here). He's very quick on his feet, and he's got a lot of experience explaining his plans to skeptical audiences. He's also a likable and, while I don't know him very well personally, decent-seeming guy. He's repeatedly won reelection in a moderate district. Democrats underestimate his political skills at their peril.

10. Everyone always says they want an election focused on the issues. For better or worse, we've got one.