Okay, an update! 
I was waiting for the migration because the forums are already on vBulletin and they started sending me teasers on vBulletin 5 (or Connect as they are calling it). That was a few weeks ago. Well, they have finally released it and they have an online demo of it here: http://www.vbulletin.com/vb5demo/
Simply put, it SUCKS. I could go into why, but the demo speaks for itself. Plus, this is the Xenforo forum and its all about Xenforo, just as it should be.
The decision is a no-brainer now, and I will be migrating the entire site over to Xenforo by the end of October. The 104,000 posts are easily manageable by the excellent vBulletin 4 to Xenforo importer. There are two queries you need to run (and maybe more depending on your bbcodes) to correct post counts, and to fix orphaned tags like the embedded video and signature tags. But the process still takes under three hours and is complete. The code in Xenforo is so easy to modify, and the code and templating system and the Admin back end is like a webmaster's paradise.
I wish Xenforo a long and healthy life after Internet Brands gives up their foolish and hissy legal action. If vBulletin 5 is any indication of the direction they are taking, they will have nothing to worry about because WHO would try to imitate such laggy, bloated software?
Anyhoo...GateFans will be migrating to Xenforo permanently. GO XENFORO!
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