Well, a lot of Labour's commitments (like the investment bank) are supposed to be built up over two parliaments.
All of them? No, probably not. But most of the core promises they make - a 26% corporation tax, a nationalised rail service, a slight increase in tax for those earning over £85k, scrapping tuition fees were either government policy until very recently or are done perfectly effectively in other countries with comparable economies. None of these look particularly revolutionary or unrealistic to me.
I'd be very surprised if an immediate rise in minimum wage to £10/hr ends up being as practical or easy as Labour's leadership seems to think it is though. Ditto for their promises about the debt. Although Labour historically has borrowed far less than the Conservatives (and paid off more debt - the idea that Labour has always been the party of borrowing is a myth), I really don't think they would inheriting a situation where that is possible alongside some of their other commitments.
So, some of them yes. All of them no.