The true meaning of this holiday is for the surviving comrades of Union soldiers to honor those who died during the Civil War by decorating their graves with flowers and other decorations. That's it. It was called Decoration Day until after WW II when the more fitting Memorial Day was used by many, and wasn't even an official holiday until 1967. It has come to mean many things far and above the honoring of dead Union, and shortly thereafter, Confederate soldiers.
Of course, first and foremost, it is to honor those who have made the ultimate sacrifice for America. But if Obama also wants to use this holiday to have us do, "all we can to repay the debt we owe to those men and women who have answered our nation's call by fighting under its flag," I certainly don't have a problem with that, especially since Armed Forced Day has never done that. Armed Forced Day is day to celebrate and honor the armed forces itself, our military might, not necessarily the individual soldiers within those forces. Nearly every country has an Armed Forced Day, and while many have tried to copy it, none have a Memorial Day with the history and traditions of ours.
While some people feel Memorial Day should be moved back to the 30th of May, it was moved to the last Monday in May for more than merely the convenience of a 3-day weekend, though that was certainly a part of it. It was moved there because people had gotten away from observing it. It was no longer the solemn day that was intended. Some feel angry that it is not treated as a day of solemn remembrance, but is instead used for block parties and baseball games and car races and picnics and family get-togethers of all kinds.
I think a celebration of America and of the American Way of Life is precisely the way it should be celebrated, as that being the best way to celebrate and honor the men and women of the American military who made the ultimate sacrifice, as well as the men and women who are currently making a sacrifice, in enabling us to have such a celebration. Obama has a lot of eyes on him right now, and whether you agree with him or not, a lot of people listen to what he says, so if Obama's words causes a few more people to go out of their way to thank a veteran, a current member of the armed services, or give thanks at the grave of a soldier, I can't see how that can be a bad thing.