Well, one difference for sure is that Edwards is not going have food at the table when sitting with the big lobbyists from pharma and insurance companies, or else they will try to snatch it all!

I find this contention overwrought.  Here is why.

1. Clinton is quite obviously a pioneer when it comes to UHC.  She championed it when nobody else did.  It has always been THE most important issue to her, whether Edwards runs or not.

2. She co-developed S-CHIP, which aims to cover all children with Universal Care.  S-CHIP was designed with loopholes to allow states to turn it into a defacto Universal Health Care plan for all.  For instance, in Minnesota S-CHIP primarily covers adults (to the tune of 87% adults) with many of the other states expanding S-CHIP coverage to adults as well.   Clinton's work on S-CHIP has been ongoing for many years, and her recent bill (currently in Congress) aimed at expanding S-CHIP to more and more adults, triple the budget, and expand maximum wage requirements for coverage to four times the poverty line (approx. 80,000/family of four.)  Edwards has no bearing on this program, which in essence is the ongoing effort by Clinton to bring UHC to more and more citizens (kids and adults) and expand it further and further until it essentially becomes a de-facto UHC system for many states and all its citizens.

3. The timing is absolutely smart.  I personally find it curious and low-effect to release a plan or program early on in the campaign.  Should it not be released for maximum impact when most people pay attention?  We are not criticizing Edwards or Obama (or Clinton) for not having many of the new plans they are unveiling on a weekly basis as we speak sometime in February or March.  You generally release your major plans in fall to capture as large an audience as possible.   That is just how it has always been.

However, I DO agree that anyone who jumps into the health care debate can only strengthen the debate and make eventual passage of a UHC system a reality.  In that sense, win or lose, I hope Edwards sticks around to help get UHC through Congress.   I am looking for him in a possible Dept. of Labor or HUD capacity, tie him back into government.  

that Krugman sees them as similar.

I agree with Krugman's analysis.

As I have previously indicated, and Krugman essentially notes, American history will show that John Edwards was the first top tier candidate for President of the United States to propose a detailed, truly universal health care plan to the voters. His leadership was a game changer. Both Obama and Clinton, the other top tier candidates, were forced to respond, and then chose to offer their own detailed plans.

History will also show that Hillary Clinton in particular started the presidential race with a different approach, a cautious approach, an "end of my second term" approach. At the very first presidential candidates' forum on February 21, 2007 in Carson City, Nevada, Hillary Clinton told the nation:

Well I want to have universal health care coverage by the end of my second term. And with everybody working on that. I think we can do it.

Speaking to the overflow crowd in Carson City, immediately after her appearance (preempting the crowd's ability to watch the other candidates), Hillary Clinton repeated her "second term" formulation:

We're going to have universal health care by the end of my two terms.

The unmistakable conclusion to be drawn from her public position was that Clinton was NOT planning to release a detailed plan for universal health care, and run for president in 2008 with that detailed plan.

At some point, she and her campaign changed their collective mind on this. They decided it was going to be a first term thing.  I find her/their decision very interesting...unexpected even...and also a game changer.  

The terms of the universal health care debate (at least for the fraction of America that is actually paying attention to all of this...10%?) will now shift to:

a) Whose plan is the best?  
b) Which of the three candidates has the best approach to ensuring that universal health care will actually be passed in 2009?  
c) Which of the three candidates is the least likely to compromise with their veto power and bully pulpit, such that the universal health care legislation that finally passes is what the people and principle demand, rather than what lobbyists and wiggle room allow?

The debate on the first question has yet to really be joined.  But on the second and third question...

History will again show that Edwards is the first top tier candidate for President of the United States to throw down the gauntlet, to really address, to tackle head on, questions "b" and "c."  This presidential candidate is serious.

In a speech given on September 17, 2007, before the Laborers Leadership Convention in Chicago, Edwards explained to the nation his proposal for ensuring that universal health care will be passed in 2009:

on the first day of my administration, I will submit legislation that ends health care coverage for the president, all members of Congress, and all senior political appointees in both branches of government on July 20th, 2009 - unless we have passed universal health care reform.

I have noticed that partisans from other campaigns have criticized Edwards for being so bold as to offer an actual approach to ensuring passage in 2009. But the irony is that this single Edwards proposal is perhaps the greatest game changer in the whole universal health care debate.  

Yes, Congress would have to pass such legislation, and Edwards would then sign it, but think about Edwards' approach here. If Edwards becomes the nominee, it is virtually assured that every Democrat running for Congress will adopt Edwards' position.  Universal health care passage by July of 2009 would become the de facto position of the Democratic Party.

Still a naysayer?  For you naysayers...even if you assume that a handful of Democrats running for Congress would be shy about explicitly promising this when they run in 2008, if Edwards explicitly and repeatedly tells the voters that this is what he, and the country will do if he is elected, and he wins the election of 2008, it is highly unlikely that Congress will be able to resist his explicit mandate. If the American people want universal health care in 2009, they will get it.

Lastly, on the issue of compromising, and settling for "a watered-down, sausage universal health care", Edwards has again laid down the gauntlet in that same speech:

I will not compromise on universal health care - not on coverage, not on quality, not on cost. I'll fight for it with everything I've got.  ... There are four principles that have to be met: it must be truly universal. Anyone who has health care must be able to keep it, but they should pay less for it. Anyone who doesn't have health care must get it, with help if they can't afford it. Doctors and patients, not insurance companies and HMOs, must have control of health care decisions.

It's going to take some time, and probably some expensive polling by Clinton and Obama to fish out the voters, (to determine if the MSM has reached them about Edwards' positions), but I predict today that both Obama and Clinton will again follow Edwards' lead, and substantially adopt John Edwards' positions on questions b and c.