My First impressions, Xperia X:

• Update through command line went through beautifully, no stuck notification, no problems with previously updated webkit package.
• I like the gallery layout – the previous layout wasn't my cup of tea. Have not spend more than a few seconds there, though. Did not try camera.
• Boy, does the keyboard sound get on my nerves. Such a small thing, yet so irritating for me. EDIT: as has been pointed out: This is a OKBoard bug.
• Fingerprint unlock does not work great for me, though it could have something to do with my huge protective case. Also I was negatively suprised that you have to swipe from the lock screen before using it. I had hoped you wouldn't even have to press the power button – that would have been a nice substitute for double-tap-to-wake. Well. EDIT: You don't have to swipe, It was just not registering well for me! Still have to press Power, though.