Too many people are turning this into an immigration only debate. My evidence is speaking to brits from all over the UK over here on holiday.
Most seem to think that we vote out of Europe all the 'Eastern European Scroungers' (not realising the other Europeans who contribute to the UK) will be kicked out. I can't imagine their will be an Eurostar train waiting at every station ready to deport people back to Calais, It ain't going to happen. Some kind of deal will be done to keep anyone who wants to stay who are already here.
To be fair a lot of people are still undecided and waiting for more concrete information, as their only dealings with the EU is their once/twice a year escape from the UK weather.
One thing that would change with a no vote would be your duty free allowance and mobile telephone roaming charges - Which kick in soon.
http://www.bbc.com/news/technology-33325031