I've been a Nokia follower that fell in love with WP just because of Nokia, and I know I'm not the only one. People can moan that some guys on here seem to be more interested in Nokia than in WP/Microsoft, but Nokia themselves have simply contributed a lot to the WP following. For me Nokia comes first. I kinda liked WP when it first came out, but all those early phones that ran it (by LG, Samsung, HTC) were just so boring...
That said, I also really like Microsoft and especially the products and services that they have been creating lately. Windows 8 is awesome, WP8 is awesome, the Surface is awesome, Skydrive, Outlook, Office, all really good and imo underestimated by the general public.
The HTC 8X and 8S are the first HTC phones that I really like, they look fresh and it's clear that some efort has been put into the design (whether or not they took inspiration from the Lumia range is another thing). However, I think overall they do not match the uniqueness and innovation that Nokia has been showing with the 920 and to a lesser extent with the 820.
But what it ultimately comes down to is that you simply can't go wrong with either device (920 or 8X), because they are both great flagship phones. For the first time, WP has two models from two manufacturers that really stand out and represent WP in the best possible way. The decision between the two can only be based on the little things: it might be size/weight, storage, camera, price/availability, super sensitive touch or, in my case, some personal preference for the manufacturer. The privilege to have a choice should be celebrated.
The 8X and the 920 are being compared to each other all over the internet, which generates attention and also a sense that WP is really something that matters these days. Eventually Nokia will benefit from this as long as they keep making decent phones.
I don't care about Samsung at all, but the same thing holds for them of course