Every president gets criticized, often cheaply and on spec, for his well-earned August vacationing, but the flak increases when he rests while the economy tanks, and his favorite spot does not sit well with hoi polloi. A week at Kennebunkport in rough times was more harmful to George H.W. Bush than a month at Crawford, Texas was to George W. Bush when the economy was humming.
All that said, Obama's advisors erred more than usual in the Martha's Vineyard choice. As a man of the Left, Obama has spent nearly three years slamming the wealthy with canned Huey-Long them/us demagoguery (e.g., spread the wealth, billionaires and millionaires, corporate jet owners, unneeded income, pay their fair share, at some point making enough income, Super Bowl and Las Vegas corporate junketeering, etc.). So he is now earning the additional wage of hypocrisy by enjoying the very perks and haunts of the class he has most demonized. The 9.1% unemployment rate, crashing stock market, the debt downgrade, the no-growth economy, massive deficits and unsupportable debt, and explosive rises in fuel and food costs—all that should suggest to a populist Democrat to stay on the White House grounds, or go up to Camp David, or spend a few days back at his house in Chicago. And when he announced that he will finally present a plan of salvation—after 10 days at Martha's Vineyard—the PR only gets worse: golfing and beach walking will be seen as taking precedence over saving jobs.
Of course, these are mostly appearances, but they matter politically. And in that regard, they confirm prior Vail/Martha's Vineyard/Costa del Sol First Family get-away preferences. In Hard Times, at best a certain Marie Antoinette unreality is conveyed, at worst the images are hypocritical to the core: what is bad for thee, is very good for me. It turns out that to pay the $50,000 partial tab for his beachfront getaway, the President really does need his "unneeded income".