Eh, as long as they vote the right way...
Well, that depends on who is in government at the time. Cameron has landed himself in hot water this weekend by insisting that the UK is a christian nation, thus illustrating the wide gulf between the "ruling tory classes" and the vast majority of normal inhabitants of this nation, who quite frankly give litte shits about religion save for presents and days off.
Oh, and Owlbread, BBC Radio 2 had a fascinating news story that suggested at the moment, only 36% of people polled would vote yes, but this would jump massively to a awesome sounding 49% if the Conservatives were to win the next general election. So, as bad as it sounds, you better hope that the Tories have a good showing over the coming months, though with Labour being led by an inflatable dartboard, LibDems getting owned by UKIP at every turn, and UKIP, well, being UKIP, this doesn't seem so hard.
With regards the compulsory voting, I think that the right not to vote if you dont want to is an important one. However, this does open up the minefield like we had with the devolution vote in here in Wales - the turn out was sub 50%, and of those that voted, only 52% or so went for yes, meaning that we have a devolved assembly based on the will of around 25% of the people. Maybe the outcome of a referendum should not be valid unless there is some arbitrary minimum turn out or proportion of possible votes being cast for a particular option, though that does open up the can of worms of what to do if the result is held to be null and void...