Australian carrier Telstra let it slip that HTC is working on an Android 4.1 Jelly Bean update for at least two of the One series smartphones - the One XL and the One S (those are the two Snapdragon S4-based One droids).
Owners of the Tegra 3-based One X shouldn't worry - Telstra Australia carries only the XL version, so they wouldn't list update info on the One X anyway.
The info on the carrier's site is pretty scarce - HTC is preparing the update but even Telstra doesn’t know when it we will get it. And when they do get it, they'll put the update through a testing phase before pushing it out to its users.
You can keep an eye on this page for any updates on the release date of Android Jelly Bean for the HTC One XL and One S.
There still isn't an official roadmap from HTC that details which phones will get Android 4.1 and when. As for the unofficial channels, XDA-Developers is already showing results.