This is the UFC's super fight. Jones is the new generation and Silva's career is coming to an end. There is no reason to try and end Spider's legacy by having him move up a weight class and fight someone like 12 years his junior. The fight with GSP has been in the works for years and the two are UFC's old guard. GSP might not be as close to calling it a day, but at catchweight, this is the Mayweather/Pacquiao fight of MMA.
I really hope it happens, and I hope Anderson Silva vacates the title for it, GSP beats Condit and we see it at catchweight. GSP still has some more WW fights to go and I think the WW division could do with straightening out, but I don't really care if Silva beats Weidman or anyone else at MW, and with the exception of a fight with Evans I don't see anything else boosting his legacy forward except fights with say Jones, GSP or Diaz. So much makes sense for this fight, so if it happens, he will concrete that GOAT name.