I got an invite on the 13th of August, but only just got some free time to try it out.

Only issue I ran in to was getting the password to enable the debug mode.
luckily one of the other forum threads had a link to a site with the password:
(http://www.entourageedge.com/forums/...ght=turn+debug)

Once that was enabled had no problem connecting the app inventor to the device.
Am looking forward to playing around with it more