Here's an AP story on this issue:
The Associated Press: Fact Check: Obama and the gas taxes
Basically, the facts of this story are right. Obama did the same thing in Illinois that he's criticizing Clinton and McCain for. Obama says he learned from what happened in Illinois. Whether you buy that or not is up to you.
However, I would say that this does not prove that we cannot trust Obama. The Clinton's have done far far worse (Whitewater, "kitchen sink" strategy, Clinton sticking with her husband to further her own political ambitions, the First Lady being assigned MAJOR political issues (national healthcare), "sniper fire", her embellishing of her role in the Northern Ireland peace process, her support of NAFTA while saying she was opposed to it, etc
As for McCain, if we have such high standards about the truth here, then we gotta really get McCain because he recently came out and said that we fought the 2003 Iraq War to get oil. I thought Iraq was a central front in the "war on terror." I guess that shit is yesterday's news.