Best Alliance PvE Race - Discipline

[Delaisa]

I was thinking of making a Discipline Priest on the Alliance side. I can't seem to figure out which race I should go with. I want my choice to be based upon racials (not how cute they are or which appeals to me better, I don't have a favorite). I don't want a Dwarf because I already have one and don't feel like making another. Here are my choices (I don't have the Cataclysm expansion):

Human
Gnome
Drainei
Night Elf

So as a summary, I'm looking for the best Alliance race (depending on racials) for a Priest.

Help would be appreciated. Thanks in advance. =D

[Rystastic]

Gnome for the 5% additional mana. Affects Rapture gains as well as replenishment, shadowfiend, hymn of hope, and, well, your max mana.

[Abandon]

Racials don't really matter at all for a Priest. If you were really fussed, you could take Human for the Spirit or Gnome for Expansive Mind but honestly pick the race you like the look and casting animations of. That will probably have a much larger effect on your enjoyment of the character.

[Norcyz]

Gnome is probably your best bet for straight up PvE goodness. I personally like Night Elf because I do a lot of 5man pugs and being able to Shadowmeld for wipe prevention is nice. In the odd event fade is on CD it's nice for a temporary aggro drop, too.