Will it matter?

I dunno.  But that '07 Obama speech is here.
Oh, look, an embed code!:
Lotsa stuff here. Little of it is a surprise, really. Read the article, in fact, if you have a choice between one or the other, read the article and skip the video. (Better to do both, though.)

I'm not that concerned about the "manner of speaking" changing, I once picked up a semi-Beeb accent during a combined exercise with Commonwealth forces, and it can come back even today.

I am concerned about what he said.