I've certainly noticed a large influx of people on the emu servers. I've also noticed a surprising bunch of EQ1 players showing up on Rift. I'm sure WoW's seen the same thing. SOE MMOs are hardly top dog (in fact many people aren't even aware that EverQuest is still running), but that's still quite a few players looking for their MMO fix.
I'm curious how many of them will stay wherever they chose to migrate. This has to be agonizing for Sony. First they haven't been on top of the MMO heap in years with a subscriber base (I'm making assumptions here) primarily composed of die-hard fans. And though it really hasn't been THAT long since the servers went down, they have to know that some of those players from an already limited base aren't going to be coming back.
Which is why I'm a little annoyed when I see people in other threads attacking SOE for not bringing the servers back up yet. Yes, it sucks, but anyone who thinks they aren't likely working their butts off to fix the issues is being delusional.