OK, for anyone reading this post instead of all the thread comments (there is a lot), check my earlier post on the how-to on installing this update to 3.1. NOTE: I do NOT have a rooted Acer.
I have had the update installed about an hour now and here's my initial comments (aka "testing").
-- This is legit. The "Chinese" leaked 3.1 version is fine. But if getting it from a mirror (because if you are like me, I don't read Chinese) make sure the site is legit (best way, a senior member is posting the link and it has not been hijacked).
-- The install took all of five minutes and went smooth. Once you power up the Acer to the boot menu the update file is detected and it's "automatic." You don't have to do a thing.
-- You know the install is going fine if you see the little Android guy, the animated progress bar and the curved arrow and box/package graphic.
-- Although when the process is done it will boot to your home page (which indicates nothing has changed, your files and settings should have remained intact), I suggest you turn the Acer completely off, then on again.
-- As I did, check "About" in your Settings to confirm that it says "3.1" in your Version.
-- So far I have tested the following and all works:
Bluetooth (Connected my stereo headset without incident. Settings were the same as before the update.)
Weather (local) - Animated because I have an app called "Beautiful Widgets, which I highly recommend.
I went to teamcoco.com and played flash files (Conan O'Brien's show).
Speakers: I don't know how software would make a difference, but the internal speakers sound way better than before the update.
3.5 mm audio jack works fine.
An optical mouse now works via the USB port, it did not before.
microSD chip recognized and I played a DVD-converted movie file, worked perfect.
GPS activated, works perfect
Angry Birds Rio looks great (it did before) and now the sound is superb.
USB 2.0 port: connected thumb drive, works. Connected USB keyboard (Logitech), works.
Can't rave enough at how great the speakers sound now. Not sure how they did it, but guess the 3.0 audio drivers must have been deficient or not optimized to take full advantage of the speakers. (My Dolby Eq. settings were the same before and after the update, do it's not that the equalizer settings changed without my knowing about it.)
Well, hope that helps in your decision.
WARNING: Make sure your battery is fully charged when performing the update.