From Keynote to Sale?

[CocoPops]

So I'm looking to fly via JFK on 13th on way from São Paulo to London.

What are the chances of picking up a new MacBook Pro (from 5th Ave store) assuming they are announced in Keynote WWDC?
Also is the keynote gonna be on day one? I think it has been in day one historically right?

 

[Closingracer]

I think the Macbook and Macbook pro 13 inch was on sale as soon as they announced it last year. I could be wrong though...