It has been the tradition that if Inauguration Day falls on a Sunday, the public events are pushed back one day.
It is not clear to me why it is OK to decide the participants in the NFL Superbowl on a Sunday, but it is not OK to swear in a President and Vice President, but there you are.
The networks will cover the parade like it is the Rose Parade complete with interesting notes and touching anecdotes (likely supplied by the Presidential Inaugural Committee's communications staff).
After the Oath of Office is administered, the President will deliver his Inaugural Address which will be cheered or booed based, not so much on what the President says or doesn't say, but upon what the observer was pre-disposed to think of it.
Far more important than the events of today will be what actually happens in President Obama's second term. There is something known as the "Second Term Curse" which probably doesn't stand up to scrutiny, but when things go badly during a Presidency, it is more likely they will have gone badly in the second term.
Watergate, Monica Lewinsky, Iran-Contra, to name a few, all blossomed in the Presidents' second terms.
Former New York Times reporter Adam Clymer wrote a summary of these (and second term successes) shortly after the election last fall.
Nevertheless, it will be a glorious day here in Our Nation's Capitol - and it would be even if it were cold and rainy.
It's Inauguration Day and, if nothing else, we should all celebrate the continuity of democracy it represents.