These boards are not dead, they are monitored by many great posters that provide a wealth of information. If someone posts a question, they will be provided useful answer.
You may also find someone commenting on an aspect of the game, and others weigh in with their opinions.
So many of the same questions have been asked and answered, that folks may find what they need by doing what you're doing, reading the forums.
What you won't find here are useless posts like, "OMG OMG I like am teh total 7331 haCzoRz pWndaDdy!!!11!!". There is no place here for that rubbish, this crowd is a bit more mature. And if someone posts flames, they will usually get the same in return. If someone posts with polite manners, they will get the same in return.
So if you have a question about the game, we're always listening.
To finally answer your question, the last known number I've heard was around 200,000'ish. That pales in comparison to WoW that sports millions of players.
But the two games are different, each has a style of it's own. Because of that, you should check out each game, then settle in on what suits you. You can try
this and tell us how you like it.