This is going to have wide-reaching consequences no matter what way it goes. Off the top of my head, potential issues include: * Combined with the sovereign debt crisis and the migrant crisis, this could be the end of the EU (perhaps unlikely, but) * The UK leaving the EU with the Republic of Ireland staying in (there's little support for RoI leaving) could create problems in Northern Ireland * The UK voting to leave…
Certainly an interesting time to be alive. A part of me thinks we (the rest of the U.K.) should just jettison England and be done with it. They're dragging the rest of us down. [edit for clarity]
By being a net importer from the EU in trade terms, a net contributor in EU budget terms, and having net immigration from the EU? Or by not fully participating in the ever-closer political union and the Eurozone, neither of which has exactly been a huge success in recent years?
This is a complicated issue with several reasonable arguments both for the UK remaining and for the UK leaving. There is a fundamental underlying tension because the UK simply has different priorities in some areas than its European neighbours, such that while no party is inherently right or wrong, not everyone's goals are aligned.
Still, the idea that England is just dragging everyone else down is silly. That's why most of the other EU leaders have been trying, with varying degrees of subtlety, to encourage the UK to stay.