Better define what you want to do in PvE to ask what is "the best" 10 Class. Disc Priests can be absurd Healers at that level, Hunters do crazy high burst, Pally/Warrior can be seriously good Tanks, etc. For PvE Versa is NOT the
#1 stat, it's Crit to 99.71% (51 Crit), then Multistrike for DPS/Heals (with Haste on anything where you don't need the Stamina) and Versa/Stam for Tanks.
Rogue: Can no longer attain 100% dodge, sadly DodgeYou and my Rogue were 2 of the last to achieve that.
Hunter: Not as OP as it used to be but still lawls (can no longer achieve 0.13 attack speed for machine gun fire).
Priest: Much more viable than it used to be.
Warlock: More viable than it used to be.
Druid: Better than it used to be at 10, still shit Healer and meh **Boomy (even Haste stacking), Feral is good but not as OP as 19.
Pally: Great Tank, meh Healer, meh Ret.
Warrior: Great Tank, great DPS
Shaman: Used to be complete shit, somewhat better now.
Mage: Still shit as far as I know.
Monk: Haven't finished mine yet, can't comment on viability at 10.
** Balance Druid at 10 does HUGE spike damage with Starfire but the cast time makes it rough most times, even stacking Haste everywhere possible.