Well, if they do ban the good pastor, they will at least be consistent and be classing him with other US preachers that they have banned on the same grounds - such as Louis Farrakhan and non-US guys like Omar Bakhri. If I am not mistaken, there is a list of banned preachers that has been published by the government.
Whilst I personally would allow these guys a platform - and counter their views with counter arguments - I do also see the logic of the UK government in keeping out those who incite hatred.
Cheers,
Shafique