The United Kingdom's new Foreign Secretary, Philip Hammond, has warned that Britons will vote in 2017 to leave the EU unless, in the interim, the EU is willing to make substantial concessions to Britain. See an article in The Daily Mail (U.K.) for more.
Today, I don't believe the other EU member states are willing to "improve" the U.K.'s deal with the EU. Circumstances in the next couple of years can change that willingness: for example, demands for national autonomy, like those made by Marine Le Pen in France or Geert Wilders in the Netherlands. If their parties succeed in national elections, the U.K. may not be the only nation wanting looser ties with the EU.
Before the 2017 EU vote arrives, comes September 18, 2014, when Scotland votes on whether to leave the U.K. I haven't seen any analyses of how that earlier vote's outcome will influence how the U.K. (or what's left of it) votes in 2017. I've argued Scotland is more pro-Europe than England, and Scots voting to remain in the U.K. will reduce the likelihood of the U.K. leaving the EU.
