New MBA Owners: Is Lion booting up in 64 bit by default?

Considering my old 2008 Alu MacBook boots 64bit kernel natively I would assume so.

Pretty sure all the supported machines do.

Lion is only a 64 bit OS which is one of the reasons it only runs on later Intel processors and simply does not work with the Power PC architecture. At least this is what I read in the cnet review.