I must admit I'm very surprised that this poll seems to be leading significantly to an out vote. I've so far spoken to very few people who are contemplating anything other than staying in. Admittedly all within my circle of friends and colleagues, so I suppose they're likely to have similar opinions anyway.
I was instinctively a yes, and having read a fair bit in order to get a grasp on the issue I'm probably even more in favour than I was before.
Ultimately there's no right answer. We will all vote on the issues that matter to us. Each side will tell us there are great risks associated with the other option, in reality it'll be (just/at least) OK either way, but some of us may decide this isn't a country we want to live in anymore. Some might see the boosting of British industries as a key factor, others may give it less weight whilst giving more weight to the European space programme. It also raises the issues of nationhood, some fiercely defend our sovereignty whilst others struggle to grasp why it matters at all.
Basically this is a pretty big decision and quite a complicated issue.