Most importantly, provide easy access to group oriented content so that people that work, go to school, etc, can fire up the game when they get home and enjoy it for the limited time they may have to play each day. A well designed group finder ready to go at launch is a must now. Preferably cross server if there are multiple servers. It's utter folly to think otherwise.
Please learn from the mistakes of a couple of relevantly recently released mmos. Don't buy into the false rhetoric like the totally silly "cross server kills community" etc etc. Give players what they want, not what you think they should want, or what some very vocal minority thinks others should want. Hit the ground running, not sputtering out of the gate, then having to play catch up months down the road adding features that should have been there from the get go to retain subscribers that are quickly leaving.