The Spanish-language video appears to come via Mexican Android blog androidmx.net. While my Spanish leaves a huge amount to be desired, the video appears to show a near-final version of Jelly Bean that's been mashed into TouchWiz, Samsung's custom Android skin.
Have a peek at the video below for yourself -- at 2:20 you can see the Android version detailed in the Settings menu, while at 3:24 you can get a look at the revamped notification bar.
Personally, I think the most interesting new Jelly Bean feature is Google Now, which uses the potency of Google's data-mangling algorithms to deliver relevant information to you, based on things like your location or search history. You can get a glimpse at this feature running on the Galaxy S3 at the 5:36 mark.
Although this may not be the final software that arrives on Galaxy S3 phones, it's heartening to see the update appears to run smoothly, taking full advantage of the S3's quad-core processor.
Galaxy S3 owners may not have long to wait before getting a glimpse at Jelly Bean -- recent rumours tip the much-anticipated update to arrive on 29 August, the same day Samsung's expected to lift the lid on a Galaxy Note sequel.
Samsung needs to make sure the Jelly Bean update arrives soon, or its flagship S3 could soon look behind the curve, at least in software terms.
Do you own an S3? Are you gasping for a fistful of Jelly Bean goodness? Tell me in the comments or on our Facebook wall.