Best television drama of the last decade, and the only show that was appointment viewing for both my partner and me. Chalk us up as woefully disappointed by HBO... and (perhaps irrationally) reluctant to invest that amount of time into any of their other programs. I'd hate for the same thing to happen again.
Again, it amazes me that this show was cancelled simply because they figured it would be too expensive to renew the cast members contracts. On a pay channel no less. Apparently, HBO doesn't want successful shows hence the previously mentioned John from Cincinnati.
If they did bump TCI to Christmas (and they REALLY shouldn't, btw), they should promote it as a special Doctor Who TV movie. Maybe film some kind of special intro scene with Tennant and Piper (doubtful, I know)