Well, this was to be expected I guess. It looks as though Sony still considers the Vita to be relevant to today's gaming community. They have just released firmware update 3.69.
There is currently no word yet on how this update affects h-encore. It's been out since June 29th, it's now September 11. That's 74 days. Sony usually responds to hacks within a week of their release. It's possible that it took them longer to patch h-encore, then again maybe it's just an update to some of the online features. We don't know yet. But if h-encore is important to you: DO NOT UPDATE BEYOND 3.68 UNTIL WE KNOW IT'S SAFE TO DO SO.
UPDATE:
TheFloW has confirmed on his Twitter account that Sony's latest firmware update does indeed patch up h-encore, sorta...
"Ok, kernel exploit confirmed patched correctly. However the reason it was exploitable depended on an other bug, which they did not see/fix. You'll soon see what they fucked up."
https://twitter.com/theflow0/status/1039414887401906176
When asked, the Flow stated that was possible to exploit on 3.69 if using a different exploit chain. He added however that he has no plans to release a new hack for 3.69, but will be releasing the source code and write up for h-encore soon.
In any case, for all it seems that h-encore has been patched. There is no word yet on how this affects the PSTV whitelist hack. This is doubtful, since it uses PSVimgTools to install, but I cannot confirm that yet.
This is rather unfortunate, as h-encore showed us that the Vita is capable of natively streaming video footage over USB to a computer running OBS Studio and thus acting as a solution to the PSTV's compatibility issues.
At present it is not clear when or if Xperi's USB streaming plugin will be install via alternate means, such as using PSVimgTools. But it does beg the question: how hard is it for Sony to release a update or app that will allow the Vita to stream its video content over USB? Hell, such an app could even integrate the PS Vita and PS3 or PS4 or even PSTV into one system. What if the Vita had a USB streaming app that would allow it to stream video (and maybe audio) over USB to a PS3 or PS4 or PSTV running a receiving counterpart of the app, thus eliminating the need for a computer running OBS Studio. It certainly would make everybody happy!
For now, if Vita USB Streaming or any h-encore exploit is important to you: DO NOT UPDATE YOUR VITA BEYOND 3.68.
UPDATE 2: Hackinformer.com reports that the Whitelist hack still works on 3.69.