President Obama's Inauguration

I just listened to President Obama Inaugural speech. I do not remember a past Inauguration that had such widespread crowds and interest. It maybe my geographic closeness to this Inauguration versus past one, but I don't remember one that had more hype around it.
I do feel a sense of optimism from President Obama. I also feel a sense of risk and uncertainty. I am not sure that these feelings are tied together or not. In the last two inaugurations for President Bush, I felt neither a strong sense of optimism or uncertainty. Maybe these feelings of optimism and uncertainty do go hand-in-hand. Can you have one without the other? Can you have contentment with optimism?
I do know that this is a historic event and as an Air Force Officer I look forward to the future of a strong, free United States through his and future Presidential leadership.