Why are you fighting and whining about low pop/high pop servers DURING A BETA? The idea is play around, feel for the game, get an idea of what's up and down, not OMG I HAVE TO BE THE VERY BEST BEFORE I TAKE ON THE ELITE FOUR or some lame notion like that. So what the population is not in the millions, it won't matter in 2 weeks anyway.
As for the preferred server, I suggest picking what you want, or better yet where your friends are heading. Play a game for fun, not for the idea of becoming Square Enix's number one FFXIV player.
Because we want to reserve our names on the server we end up rolling in.
Don't get me wrong, I know what makes an MMO fun. Regardless of where your friends are, if the server can't support your needs, you won't have fun. And low/high population does play a key roll in the enjoyment of an MMO. Economy, group formations, class distribution all play key rolls on what you can do and how well you do it and all that is directly affected by the size of the server. So, excuse me if I'd like to increase my chances of enjoying an MMO with guys I've known for years.
Uh yeah....you're worried about a name? I think you won't have to worry about it in XIV, since, you know, I DOUBT HIGHLY THAT ANYONE WILL HAVE YOUR FULL ORIGINAL NAME. I mean seriously, if you're worried about a name, you're probably gonna use some lame anime name or one that is beyond popular (I'm looking at those jerky Cloud Strife lamebrains). I'm not worried, cuz come the day I register, Agent DeeVeeOne will be available.
In any case, how about you all just get on a server, and figure it out from there? I honestly don't think worrying about it now will benefit anyone, simply because in about 6 months, the populations will probably jump again due to PS3 users getting in. And no offense to you gentlemen and ladies, but I still don't have much faith that XIV is ready for full play yet, and many of the players will ditch during the first year. If they fix all the problems for pc in the next 5 months, once the PS3 release arrives, I expect a bevy of new ones to arise.
Long story short, don't start fighting yet, there's plenty to bicker and rage about soon enough.