They did do alot of stuff with the servers. Its possible that they are able to hold more, thats why you see less on the server main screen. I've seen alot of people online in my server.
Also, the holidays are over and its back to the RL grinde. And with SO many mmo's out there, it's hard to say. SWTOR will be around for a long time. I mean cmon, its only been a month. Just wait whats in store a year from now. It'll be a 180, GARANTEED.