As Barack Obama has pointed out, we only have one President of the United States at a time.

Until his inauguration, Mr. Obama is President-Elect. The inauguration ceremony is the official transfer of power from George Bush to Barack Obama.

Regardless of your political affiliations or point of view, Barack Obama cannot wield actual political power until he has officially assumed the duties of the office of President of the United States. Until that time, all Presidential decisions are still the responsibility of George W. Bush.

In the 21st Century we have become used to rapid transportation, but back in 1776, transportation was much slower, so it made sense for there to be a gap in the time it took for the outgoing president to move out and the incoming president to move in.

Originally, inauguration was in March, but when Franklin Roosevelt became President, the inauguration date was moved up to January. Given that history, in the future, inauguration may be moved closer to election, now that communications and transportation move at such a rapid pace.