There is an interesting post on Theatreboard from a poster who is pretty reliable (about 85% accuracy I'd say) who says the Beauty and the Beast UK tour is planning a stop at the London Palladium next Christmas. Considering the times who knows how this will pan out but this year would have been the last of the 5 season deal qdos initially had at the palladium
If true I'm sure there will be many other London venues happy to house a panto although none with the kudos that the palladium brings to attract talent.