YouGov has a poll out today which has the referendum result neck-and-neck; and that's asking the longer question as before!
All the details can be found here ... and some further blog posts about the poll results are here and here.
Come on YouGov; surely time to ask that actual question:
“At present, the UK uses the first past the post system to elect MPs to the House of Commons. Should the Alternative Vote System be used instead?”