MWC is starting this week and it's looking increasingly unlikely (based on my own speculation) we'll have a new Windows Phone 8 flagship device announced from any of the main Microsoft manufacturers.
HTC and Sony have played their cards for their flagship android devices for the first half of the year (the One and the Xperia Z respectively), and we're still waiting to hear from Samsung about any Galaxy or Note follow ups.
As I said, I'm a sucker for marketing, so that while the One and Xperia Z have been announced, the differences to my phone usage (internet browsing, messaging, angry birds, news apps) won't change that much with these new flagships as to my old flagship, nor will it change very many other peoples use. However the public perception of seeing a new flagship, the hype around it, does mean most will be loking to them for their contract upgrades over the next few months.
I get the feeling Microsoft and it's WP8 partners want to ape Apple in some ways. They want to release one flagship (per manufacturer) a year rather than a cavalcade of devices throughout the year. I really would like a Nokia 920, but it feels old compared to the Xperia Z and the One...