Because they're Mac users and are laughing at how long it took MS to catch up to their beloved UI?

It's a launch "party". They've been drinking?

It's a "launch" party and they're on the boat?

Ballmer's presentation just blue screened?

>I received an e-mail about a launch party for Windows 7.
>
>On the picture all the people there really seem to enjoy themselves.
>
>I assisted to some presentations so far on Windows 7. I never reacted the way those persons are.
>
>Why would anyone laugh that much while watching a presentation of Windows 7? ;-)