On OSX 10.9, the game crashed on me frequently - about every half hour, sometimes with a crashlog that could be sent, but often I just got a white screen and had to force quit. I play on an 27" iMac (model 2011 with 16GB RAM and a 2GB Radeon HD 6970M) at 2560x1440 with the suggested high settings. That must be fixed urgently, since Mac users don't have many options regarding MMORPGS (WoW, GW2 or Ryzom are the only ones I can think of atm), so they might be quite a big percentage of customers.
And then there were the freezes after talking to NPCs, also very frequently, There's a workaround (open your mail window), but it's a PITA nontheless. This should also have a very high priority.
On the positive side: everything else - frame rates were reasonable for that resolution, graphics the best I've seen yet in an MMORPG, and gameplay immersive and fun at all times and in all factions. CE is already bought and I'm looking forward to a long time of happy gaming.