The Storm1 that I had saw a lot of leaked builds come out. None of them were ever released by Verizon.
That being said, I do believe we will see GB for the X. That would probably be the last update Verizon will do for it.
Verizon did occasionally release builds for the S1, just like the Curve and Tour (that's all I had before I went Droid). The leaked releases were test builds, and then later revisions were released to the Storm. I didn't mean that Verizon would be releasing all of these versions of GB. I more meant that if VZ wasn't developing a GB release, we wouldn't see ANY leaked builds. There wouldn't be builds. There would be nothing. :'(
The second part of your post, about it being the last update, I mostly agree with. There's no way that they will put ICS on here, and HC isn't even designed for phones. However, I would hope that once they release this and inevitably find some bugs, they will patch (some of) them and release an update.