I checked it out a few weeks ago. You can stay in Canada six months out of the year with no requirements. If you stay more than six months you can apply for permanent resident status and you do not have to give up your US citizenship. I think at that point you are also eligible for the health care. You can also apply for citizenship. Its pretty easy in Canada.
Canada might be a a valuable backup to have if Obama’s Democrats get a second term, ‘cuz you know they’ll be going after anyone with money. Canada has the same language, culture, TV shows, companies, restaurants, sports, weather (same as northern states, anyway), etc. as the US, so it’s not so much of a shock to move if you choose.
On the downside, our goods prices are higher than the US, as are the taxes. And there’s still a lot of bleeding-heart lefties (and their politics) up here.