The significance is just that 727s fly, and Twister is being replaced by a flying attraction.
727 is Twister.
As for 620, I'd love to be wrong and hear that Star Trek is indeed coming. I'm not a fan of the franchise, like at all, but I think it could be made into something cool. I just hope it's placed somewhere other than Shrek. Such a big franchise deserves more than the randomness of Production Central.
As for the guy heading both of these, I find it interesting that he's been heavily involved in all of Universal's foreign parks except for Beijing. Means he knows how to deal with big projects.