I think Matt Smith should.
Absolutely! :) With the show being so successful on both sides of the pond it would be a good time to make a Who movie!
Not sure if Matt would have time to star in a big screen film whilst on the TV, but I'd love to see a multi-Doctor film with both 8 and 11! McGann alone as the Doctor might not bring in the crowds of not-We (although his face has appeared on screen in montages of the Doctor's past incarnations, I still get people surprised when I mention that McGann was the 8th Doctor)
Also having Smith to play against would give McGann a chance to highlight how his portrayal is different (or alike) to the other incarnations within the time constraints of a feature film, he had sooo little time to establish who he was in his début story, and most of that had him with amnesia!
I say bring him back ASAP! :D
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