Seriously

Ben Smith points out:

There was, Obama advisors point out, no low-key way to do the nomination -- you can't do it in a diner. And the Republican attacks don't depend on the reality. Still, as I wrote today, his advisors have long known, big speeches can cut both ways. That's why, at one point on the campaign, they were banished to the evenings, so that he would appear in the evening news in more intimate settings.

That's why you do it BIG and embrace it. It's going to be powerful, awesome political theater. I'm sure Sen. Obama is going to have lots of flags on the stage. Republicans are just haters.