Rohan shared his thoughts on the subject already, but I thought I'd chime in as well. I absolutely hate the "World First" feats. At least they're not achievements, but I don't think anyone should be rewarded for these feats.
First gnome to 80? Who cares. First tailor to 425? Whoop-de-do. First player on the server to 80? Way to prove you can either a) take a week off work or b) take a week off school or even worse, c) share your account with others and power level.
If I see anyone running around sporting one of the "server first" titles, I'll just laugh a little on the inside. All the other achievements I have no problem with. Exalted with the Timbermaw? Sure, it takes time (a lot of time), but you can do a little here, a little there, but it doesn't take a week of straight playing.
Also, what does happen if someone gets seriously injured from sleep deprivation or too many energy drinks? I have an energy drink here or there, and when seeing the latest Batman film, I drank too many in a short period of time and I swear I thought my heart was going to explode (why I still continue to drink even a single one is a mystery...). So what does happen if someone drinks too many, goes into cardiac arrest, and dies - while trying to accomplish a feat that Blizzard set up in game? Could they be sued? Maybe. They are officially sanctioning the race to 80. They are saying - go for it - we know you'll play 24x7, but we don't care. You want to be the server first, congrats.
I doubt they'll change their mind about this, but in my opinion, it's probably one of the stupidest things they've done in a while. Let's hope they do go back and realize the mistake they've made.