How is that bad? I mean, it's nowhere as good as old Symbians but on comparable level with the latest (I can only compare to E7 and C6 and the battery life is quite similar)

N9 battery lasts way longer than any Androids I have used... for iphone I cannot say by myself but I have heard they are not so good on it... for Lumia 920, who knows? It's impossible to say yet what the battery life will be but considering faster CPU and larger screen I am fairly sure it's not remarkably better than N9.