The station was
PADDINGTON. All the answers were Bakerloo stations, suggesting you all noticed that the colour scheme was brown.
Many of you mentioned (even some who gave an incorrect answer) that the train was going north, since there were two different destinations displayed, presumably Queens Park and Harrow and Wealdstone. This makes sense to me as it's unlikely that in a deep-level tunnel, ie in Central London or thereabouts, a southbound train would have any other destination than Elephant and Castle.
I tried to smudge out the sign hanging from the roof, directing passengers to the other lines; I left the National Rail bit intact although it is so small it's hardly recognisable. The colours of the District and Circle lines, and of the H&C, could still be visible. This sign is a big clue.
There were a lot of passengers getting off the train, as one of you mentioned, meaning it would be more likely to be a big station such as Paddington. Other than the decor and shape of the station itself, I don't think there were any other clues.
The following gave the correct answer:
editorsfoot
Lancaster Gate
gasman
jbom1
Soup Dragon
Dr Who
Starkey7
tangy
Incorrect answers:
Marylebone x2
Piccadilly Circus
Embankment
Waterloo
Elephant and Castle
Next one will be a little more distinctive.