Wow! I've been since one hour ago trying to post a message but I didn't want to do it before reading all of yours. Herculean feat, if any.
I've installed the new build last night, it's been working about twelve hours, on a Lumia 1020. This is what I have seen so far:
>> Disappeared the bug that made unresponsible the touch after ending a call.
>> CORTANA WORKS!! FINALLY!! (I'm a Spanish-speaking person). I mean, it's not that on the previous build we the Spanish-speaking could use it without speaking to her, or she didn't speak to us... No, no; it DID NOT work at all. And now IT WORKS GREAT!! She can speak and hear. Quiet hours also works, but the tile on Notifications Screens blinks as possessed.
>> The store has worked smooth since the zero minute; after updating stills works fine.
>> Groove Music was also updated, but I don't see any remarkable change. The live tile is still conspicuously absent.
>> People App remains invariant, i.e., the same crap as it was on the previous build. Twitter account contacts are still being named "BingHealthAndFitnessApp"; Skype ones are named "Podcasts", you can't pin yourself ("Me") to the Home Screen... Anyway.
>> The first time I got into Battery Saving option, while the phone was plugged in, under the charge bar I could see this: "Estimated charging remaining time: 2 hours". Then it vanished; after some while, it reappeared, but it didn't displayed any amount of time. Now it switches between that message and "Estimated remaining time:", with no amount of time either.
>> Albums functionality on Photos app are, also, conspicuously absent.