ASUS Sweden has taken to Facebook and let everyone know that users of the Transformer Prime in Sweden should be seeing an OTA update to Jelly Bean available. While there is no word on other areas, this is a good sign that ASUS is prepared to roll the update out en masse shortly. My own source "close to the matter" says we should see it in the U.S. in early October should everything go well in Sweden.
Along with the obvious perks of Jelly Bean, ASUS wants to remind everyone that they will be losing Adobe Flash official support, and that the Jelly Bean update will remove Wifi-Direct from the Prime. On that note, they also say no users will be forced to accept this update.
If you're rooted and ROM'ed, ignore all this and be ready for better custom work from your favorite developer. If you're not, you can check for the update from the device settings -- let us know if you see it!
Source: ASUS. Thanks everyone who sent this in!