Super late to the party. Hope they come up with something great. Not because i like Nokia, i hate them, but competition is always good, right.
In all honestly, i bet my salary it won't be great. An average product at an average price. It will gain minimal market share initially and struggle for growth as competition increases. Within 5 years id expect them to drastically restructure or cease production completely.
Of course it doesn't help that every new release of windows has historically been a hit and miss affair.