Beaker, I'll grant that XSV were first, but they didn't have the same impact. There are probably a few reasons for that. They were a group of players who were always a little skeptical of Xball and the NXL in particular, they never achieved much success in the NXL, they seemed to me to be quiting the moment before they were fired. I am happy as hell for them now- I always felt it was a good group of players, and they deserve success. But the NXL teams were not going to follow these malcontents anywhere.
By contrast, Miami Effect seemed to be true believers, had some success competing in the NXL and in fact played for the guy who came up with the whole Xball of wax. When they defected, other teams seemed to say to themselves "why not us" and the NXL relented.
Of course, the NPPL helped the process with the whole relegation/ limited pro division rule.