Not going this year, and don't want to ring any alarm bells, but thought you might want to check up on this: word on MTB forums is that Easyjet have dropped the 10kg extra baggage allowance for bikes (and all sports equipment), while still charging the extra 15 quid each way.
So that gives a TOTAL free allowance of 20kg. Max 32kg per single item and max 50kg total. Not absolutely clear what rate excess in charged at: the list on the page below shows % quid per kilo but not clear if this specifically to be applied to surfboards, wind surfers, hang-gliders, and firearms....
(While this isn't relevant to road bikes, they now also specifically forbid carrying hydraulic brakes and suspension units).
http://www.easyjet.co.uk/en/Book/regula ... ml#baggage