As stated above – new policy for cabin luggage
http://www.easyjet.com/planning/cabin-baggage
Our cabin bag guarantee means you can make sure your bag travels with you in the cabin, even on the busiest flights.
To take advantage of the guarantee, simply bring ONE slightly smaller bag no bigger than 50 x 40 x 20cm including handles and wheels and we’ll guarantee it will travel with you either in the overhead locker or, if necessary, under the seat in front of you.
You can still choose to bring ONE slightly bigger bag up to the maximum size of 56 x 45 x 25cm including handles and wheels, but on some busy flights your bag may have to go into the hold.