As the Wall Street Journal writes:

There’s no excuse in particular for letting the White House claim that Mr. Ryan would “end Medicare as we know it” because that is demonstrably false.
Late last year, Mr. Ryan joined Oregon Democratic Senator Ron Wyden in introducing a version of his reform that explicitly retains Medicare as we know it as a continuing option. The reform difference is that seniors would for the first time also have a choice of government-funded private insurance options. The Wyden-Ryan belief is that the choices resulting from private competition will be both cheaper and better.
This “premium-support” model has a long bipartisan pedigree and was endorsed by Democratic Senators John Breaux and Bob Kerrey as part of Bill Clinton’s Medicare commission in 1999. Wyden-Ryan is roughly the version of reform that Mr. Romney endorsed earlier this year.

James Pethokoukis, working from a suggestion by the American Enterprise Institute’s Andrew Biggs, lists the 3 things that need to be stated over and over about the Ryan Medicare Reform plan:

1. No one over the age of 55 would be affected in any way.
2. Traditional Medicare fee-for-service would remain available for all. “Premium support”—that is, government funding of private insurance plans chosen by individuals—is an option for those who choose it. No senior would be forced out of the traditional Medicare program against his will.
3. Overall funding for Medicare under the Ryan-Wyden plan is scheduled to grow at the same rate as under President Obama’s proposals. Is this “gutting Medicare” and “ending Medicare as we know it”? In reality, it’s the market giving seniors cheaper, higher quality choices they can take if they wish, with the traditional program remaining an option.

Back in 2010 President Obama called the Ryan-Wyden plan a “serious” and “legitimate” proposal (though, as Ted Nesi points out, Wyden does not agree with the latest iteration of Ryan’s plan). The President also pointed out the “political vulnerability” that all such proposals have, even decrying the tendency in Washington, D.C. for one party to scare seniors, etc. instead of dealing with the proposals put forth by the other. Honest, here’s the video (at around the 4 minute mark).