Well it doesn't match up with what other reviewer have said. also I don't find it remarkably unlikely at all, but then I'm used to the remarkable ability of WP to save on battery, whereas my current android will eat battery even if I don't use it, and if I try to use a GPS app or play a game... then it's gone in a second.
I was only pointing out the reviews, which nearly all mention that it has poor battery life. Even the most favourable reviews only puts the battery life at little more than a day, which is pretty terrible for a phone without a changeable battery. Even accepting that WP is better with battery life than Android - which I'm not challenging - we're still talking about matters of degrees rather than factors. Lasting around a day is still bad by any objective measure. It means you have to moderate your usage and be looking to recharge it whenever possible. Most of the positive reviews that you mention base their praise upon the specs rather than real world usage - on paper it's a reasonable battery but lasting at best a little more than a day is poor.
Don't get me wrong, I think it looks like one of the best phones on the market but the lack of a replaceable battery and its weight give me cause for concern. It wouldn't be as much of an issue if I could simply carry an extra battery or two around to be safe, which I do with my current phone. Sometimes I like to play games while I'm out and about and carrying an extra battery allows me the flexibility to do that - with the Nokia Lumia 920, Apple iPhone 5 or the HTC One X you can't do that because of their non-changeable batteries.
The Lumia 920 ticks most of the boxes and the wireless charging facility is brilliant but by the time my contract expires in about 6 months I'm sure they'll be something better on the market.