"The leak" you are referring to is not a Verizon build/RUU. It's an aftermarket build based on a test build done in April.
Until one or two actual RUU leaks have been released, don't hold your breath. And that process usually takes a few weeks. I'm going to guess that we aren't going to see ICS in September, or if we are it'll be very late September.
Yup, that's about what I'm thinking if the update doesn't get cancelled instead. Even if it does roll out, there will be bugs and how long will it take for a subsequent update to roll out (if it ever does)? Myself, I can't quite understand why Verizon/HTC are even considering rolling out a major update for a phone that's a year and half old, is already very stable on its current software and where a vast majority of its owners are no longer under warranty. It's just asking for trouble IMO.
Anyway, just saw this this morning:
4 Reasons Why the HTC ThunderBolt ICS Update Could Be Late:
4 Reasons Why the HTC ThunderBolt ICS Update Could Be Late
1. HTC and Verizon completely missed the July upgrade window for the HTC Rezound and then pretended as if nothing happened when it released the software in early August instead. It?s clear that neither company has any problem breaking update promises.
2. HTC?s Facebook account has stopped telling ThunderBolt owners that August is still in the cards. Instead, it has been extremely vague about the update?s arrival.
3. Verizon?s website remains without an HTC ThunderBolt ICS update changelog, something that is usually posted ahead of a widespread roll out.
4. Verizon may have learned that hitting the deadline for the sake of hitting the deadline probably isn?t as smart as it sounds. The Droid RAZR and Droid RAZR MAXX updates were released on the last day of their promised update window and both pieces of software are plagued with bugs. So, it?s possible that HTC and Verizon want to avoid something similar. (The HTC Rezound update was smooth, from what I can tell.)