The Nokia Lumia 900 is the Finnish manufacturer's flagship Windows Phone. So a drastic price cut is big news.But right now, that price cut is in the US, rather than the UK. Over in the US, the phone is now available at half its original price with network AT&T – $49.99 per month over two years, instead of the original $99.99.Why the sudden price drop? The general consensus seems to be the lack of an upgrade path to Windows Phone 8 later this year. Basically, consumers are thinking twice about committing to a new phone that could be (almost) obsolete in a matter of months.It is something we hinted at in our recent review. The phone itself is impressive and eye-catching. But the inability to upgrade really does hinder its prospects. With that in mind, could a UK price drop also be on the cards?As yet, nothing has been confirmed, with the £30+ monthly contract price still holding at the networks. Perhaps because Nokia isn't abandoning the Lumia phones with Windows Phone 8 – some new features and upgrades will still land on the existing phones. But as the launch date of the new Windows platform gets closer, you would expect the price of the Lumia 900 to drop steadily. Or even, like in the US, quite abruptly.