By the way the OFT has approved the GB merger today.
The following is also mentioned.
"It noted the remaining competition on routes from London to Alicante/Murcia, Malaga, Faro, Ibiza, Mahon, Palma and Marrakech was not enough to dismiss concerns.
However, the OFT concluded: "The likelihood of further entry and/or expansion on the routes is sufficient to constrain the parties [easyJet and GB Airways] post-merger."