I don't think this will pass. The way Swiss citizens get to vote on such things is really wonderful to see but they're an educated bunch and I think ultimately they'll realise that this helps to stimulate the economy. With the strict regulations they have in place such as Basel III and the reserve requirements etc it should be safe to assume that banks can operate with relatively little risk and still stimulate the economy through that.
I don't think it will pass either. But at least they will have had a debate in public about the meaning of money and the meaning of debt.
The way their referendums work it will be a public decision and not a government one so when you say public it really will be the public. It's one of the great ways that the Swiss become so well educated, because they have such a large input in to decisions.