I'm rather perplexed by it - even ignoring the fact that it's intended to be paid for with the magic money tree of a tax on bankers' bonuses (which Balls has already spent about five times over, has he not?).
Surely it's not within the Government's gift to 'guarantee' a job? Unless they want to employ an army of litter pickers or similar. If they want to achieve through free market employers like Tesco, surely loads of people are going to have a little cry about the Government 'subsidising' a company that already makes billions of pounds in profit (as some say already happens anyway)?
Here's a link for you to not click: http://www.theguardian.com/politics/2014/mar/10/labour-tax-balls-bonuses-jobs-young