So here's the deal. I've listed everyone I know of who was ever a regular member of the Justice League in all their various incarnations. I'm sure I've missed some, so feel free to correct me. Everyone's input is

.

And yes, I did include the members of the upcoming series. I figured it couldn't hurt since we know they will actuall be appearing.
At any rate, rather than do some long drawn out +1/-1 with so many rules no one can follow, I figured we'll keep this simple. Take the list below, list your top 20, voila. Just fun and simple, no big deal. Have fun!
Adam Strange
Agent Liberty
Amazing Man
Animal Man
Aquaman
Atom
Atom Smasher / Nuklon
Aztek
Batgirl / Oracle
Batman
Batwoman
Big Barda
Black Canary
Black Condor
Black Lighting
Bloodwynd
Blue Beetle
Blue Devil
Blue Jay
Booster Gold
Captain Atom
Captain Comet
Captain Marvel
Congorilla
Creeper
Crimson Fox
Demon / Etrigan / Jason Blood
Doctor Fate
Doctor Light
Elongated Man
Faith
Fire
Firehawk
Firestorm(Ronnie)
Firestorm(Jason)
Flash (Barry)
Flash (Wally)
General Glory
Geo-Force
Green Arrow(Ollie)
Green Arrow(Conner)
Green Lantern(Hal)
Green Lantern(John)
Green Lantern(Guy)
Green Lantern(Kilowog)
Gypsy
Hawkgirl (Kendra)
Hawkman
Hawkwoman (Shayera)
Hourman
Huntress (Helena Bertinelli)
Ice
Lightray
L-Ron / Despero
Major Disaster
Manitou Raven
Martian Manhunter
Maxima
Maya
Metamorpho
Mister Miracle
Mystek
Nightwing
Obsidian
Orion
Phantom Stranger
Plastic Man
Power Girl
Ray
Red Tornado
Red Arrow
Rocket Red (Dimitri)
Sargon The Sorcerer
Silver Sorceress
Steel (Hank Haywood)
Steel (John Henry Irons)
Powergirl
Starman (Mikail)
Supergirl
Superman
Tasmanian Devil
Tomorrow Woman
Triumph
Vibe
Vixen
Wonder Woman (Diana)
Wonder Woman (Hippolyta)
Zan & Jayna (The Wonder Twins)
Zatanna
Zauriel