The European Galaxy S III Jelly Bean update first turned up in Poland about three weeks ago. At the time, we were hoping it was a good indication that the rest of Europe would follow soon after, but that's about the last we've heard of it until today. In the meantime, Samsung did fire up the update in Korea and reiterated it would soon show up in the States.
A new Android 4.1.1 build I9300XXDLIH just surfaced, this time destined for Sweden. The CSC (Consumer Software Customization) for this release is I9300VDSDLI1 which appears to point in the direction of unbranded handsets. If you have a compatible device, you can attempt to flash the firmware using ODIN, check Kies in case it's available there too, or head over to this XDA post to discuss the release.
Hopefully, this means Samsung has fixed all the bugs it found during the Polish rollout and we can expect a wider release this time around. Otherwise, third time's the charm, right?