I mean Rose Tyler was Billie's 1st acting so she was relatively unknown and I'd not heard of Freema before Dr Who. The only assistant who's really been known before was Catherine but she wasn't really known as that kind of actor.

There is going to be some trepidation over the changeover. I remember being nervous about Tennant, and it took awhile before he grew on me. That being said, the show as a whole has gone further and further downhill. Characters and events have been contrived and shallow. The show has been more of a fanboy orgasm than a legitimate show standing on it's own; it's a caricature of Doctor Who. For the most part I blame this on RTD, so I'm hoping that his departure will give the series life again. I think the casting choices have been a good indication that they're looking to shake things up a bit. That's a good thing, at least as far as I'm concerned. It suggests a new direction that is desperately needed at the moment.

From the promo shots I can picture a potential Doctor Who direction that I really like. I'm officially excited now and await 2010 with bated breath.

I trust Moffat's judgement, so I guess we'll just have to wait and see.