Also does anyone know if the US version has aired yet, as I think it was supposed to start back in April?
looks like we will also soon be able to watch the US version

WDYTYA? USA
Hollywood stars Sarah Jessica Parker and Susan Sarandon will discover their family history for the American version of Who Do You Think You Are?, due to begin in late May 2009.
Former Friends star Lisa Kudrow, who is executive producer of the series, will also unearth her roots in one of the six episodes to be screened on American channel NBC.
Kudrow says: 'The show personalises history and turns it into a gripping narrative. The most amazing thing is the realisation of how connected we all are.'
The BBC plans to broadcast the series here later in the year