I doubt it. If anything extra is to be announced I think it would be the new iPad's.... We will just have to wait till Sep. 10th to find out for sure, though.
Very doubtful. Typically Apple has separate events for iOS devices and computers. The upcoming announcement will be for iOS devices - iPhone, iOS 7, and hopefully iPads. There’s a possibility that Apple will just release the new Macs without an event, but with the tremendous step in battery life, the imminent release of the new Mac Pro and whatever else Apple has cooked up, I expect a Mac event, as well... but I don’t see the Mac event being any way connected with the 9/10 event.
I agree with Fausty that Apple might just put the new Mac's out without holding a event. So far I've been seeing a lot of sites pointing toward a Oct. release.