I agree, Windows 8 is the snappiest mobile OS I have come across. Got my parents the Nokia Lumia 521 (for $120 @ Walmart - an absolute steal) and they love it. Big tiles, information right on the screen, offline maps, easy to use etc.

However there are still some downsides you need to be aware of if you planning on getting one:

[1] Windows is highly paranoid about security (Irony), no application can access the call logs, messages or even basic settings such as brightness etc. So don't expect to find apps that customize your phone to your liking.

[2] Apps - Saw your friend using that awesome Starbucks app and want it? Nope you won't find it on the store like many many others. To make it worse, Google is hellbent on never creating apps for Windows Phone. Luckily there are better or acceptable alternatives for most of their core products.

[3] Phones - Not many choices. If you want a solid phone stick with the Nokia brand. The exclusive apps will itself win you over.