One stunt is detailed in the NY Post. Get ready for some single-payer love in his upcoming film:

Filmmaker Michael Moore's production company took ailing Ground Zero responders to Cuba in a stunt aimed at showing that the U.S. health-care system is inferior to Fidel Castro's socialized medicine, according to several sources with knowledge of the trip . . .

. . . But the sick sojourn, which some say uses ill 9/11 workers as pawns, has angered many in the responder community.

"He's using people that are in a bad situation and that's wrong, that's morally wrong," railed Jeff Endean, a former SWAT commander from Morris County, N.J., who spent a month at Ground Zero and suffers from respiratory problems.

(via a reader tip)

Update:
Coverage for Sicko continues with here on Kevin, M.D. more discussion and debate:

Sicko: Real health care in Cuba

Health insurers are bracing for Michael Moore

Update 2:
More coverage from around the blogosphere.

Michelle Malkin:
"While we're on the subject of Cuba, Michael Moore, and far Left propaganda, Cuban bloggers are exposing the lies about the Castro regime's Communist health care system."

Captain's Quarters:
"This movie seems to be a paranoia-fest beyond Moore's previous accomplishments. Does he wants to prove that the American health-care system is somehow in cahoots with the Bush administration over the 9/11 attack, or does he just want to show that American health care is incompetent? Certainly, he's looking to boost the tired leftist propaganda that Cuba's free health-care system is a model for America to follow. One might think that Moore's argument here would have been undermined by Fidel Castro himself, who had to import Spanish physicians to treat him in his extremity earlier this year."

The Opinion Mill:
"After decades of paralysis brought on by conservatives screaming about socialized medicine, the country finally seems ready to talk about a rational health care system for America. If Sicko turns out to be more schmuckery along the lines of Bowling for Columbine, the movie will only help to muddle a long overdue debate."

Health Care BS:
"As it happens, one of my colleagues at the hospital is a Cuban-American whose father fled to the U.S. after Castro’s takeover. She has many relatives still there, and it is impossible to exaggerate the contempt she has for Americans who think Cuba’s health care system is superior to ours.

In her eyes, the only thing more despicable than Castro’s regime is the “progressive community” that continues to lie on its behalf."

Six Meat Buffet:
"Who knows, taking on Bush is popular. HMOs? Maybe not. The newness was exciting with “Roger and Me”. But this “man of the people” schitck probably won’t play well outside the college demographic."

Lerterland:
"It's one thing to make the case for a single-payer health care system. But when you consider the effects of arbitrary arrest and imprisonment on the health and welfare of an individual, it is perverse to laud Cuba for its social services.

Moore, as always, is catching hell from right-wingers. For this reason, he will feel vindicated. He shouldn't, because his apologetic stance toward Castro runs afoul not of conservative principles, but liberal ones."

The Spine:
"As it happens, Moore went to Cuba with sick Americans who can't -- because of not having health insurance or other reasons -- get treatment for their illnesses. Cuba, as you may recall, is a medical care paradise. Just like the old Soviet Union was, and -- of course -- China."

Fictions and musings, with a side of yuca:
"Whatever that film claims, the truth is that while Cuba may have the lowest infant mortality rate in the Americas, it also has the highest abortion rate (32 out of 100 pregnancies are aborted). And while healthcare is certainly free to everyone, Cuban hospitals lack simple drugs like aspirin for their patients."

Blog For Cuba:
"One of Fidel Castro's biggest propaganda successes has been the acceptance as fact his lie that Cuba has the best healthcare in the world. I could link story after story that proves Cuba does not provide good healthcare for its citizens, but the most telling proof of all is the fact that after his emergency surgery, Fidel Castro himself chose not to trust Cuban healthcare providers, but instead arranged to fly in a prominent Spanish physician along with the latest equipment to tend to his medical needs."

Update 5/20 -
The Toronto Star:
"We Canucks were taking issue with the large liberties Sicko takes with the facts, with its lavish praise for Canada's government-funded medicare system compared with America's for-profit alternative.

While justifiably demonstrating the evils of an American system where dollars are the major determinant of the quality of medicare care a person receives, and where restoring a severed finger could cost an American $60,000 compared to nothing at all for a Canadian, Sicko makes it seem as if Canada's socialized medicine is flawless and that Canadians are satisfied with the status quo."

The Boston Herald:
"But possible Republican presidential contender Fred Thompson is already having some fun at Moore’s expense. The “Law & Order” actor and former Tennessee senator has Web-posted a video clip of himself sitting in a big leather chair, puffing a cigar and reminding Moore that Cuban dictator Fidel Castro once dealt with a documentary filmmaker by locking him up in a mental institution.

“Mental institution, Michael, might be something you ought to think about,” Thompson deadpans.

Somehow we think the ever-tedious Moore has finally found a worthy adversary - one who can put nonsense into perspective."

Update 5/22 -
Lynn Davidson:
"Moore started with a stunningly stupid statement that essentially told these socialized medicine ingrates to quit their whining about 18 month-long waits for gallbladder surgeries because it means they apparently live three years longer...somehow. Moore lashed out at these legitimate questions about his habit of propping up an unrealistic portrayal of a socialist utopia (or communist, in Cuba’s case) by minimizing the citizens’ hardships."

Rich Lowry:
"Cuban health care works only for the select few: if you are a high-ranking member of the party or the military and have access to top-notch clinics; or a health-care tourist who can pay in foreign currency at a special facility catering to foreigners; or a documentarian who can be relied upon to produce a lickspittle film whitewashing the system.

Ordinary Cubans experience the wasteland of the real system. Even aspirin and Pepto-Bismol can be rare, and there’s a black market for them. According to a report in the Canadian National Post: 'Hospitals are falling apart, surgeons lack basic supplies and must reuse latex gloves. Patients must buy their sutures on the black market and provide bed sheets and food for extended hospital stays.'"