Mostly because hes young and a good speaker, I dont know why it accelerated out of proportion so quickly though. It's probably a combination of the ending of the term of a very unpopular president (Bush), a switch of political parties, the perceived intelligence of Obama displayed by his speaking skills, and also the fact that he's the first black president. The media, I'm sure, also played a very large role in getting people excited about Obama. For example, I hate to admit it, but had it not been for all the media hype, I probably wouldn't have watched the inauguration. But with all the TV coverage Obama was getting, I felt like I'd be missing a spectacular event if I didn't tune in.