I picked up the Boba and Clone, and I fear I am already hooked.
I thought it would be helpful to have a list of what all is out there so far, so I made one based on what I have personally seen or seen pictures of. I could certainly be missing some things though, so please let me know if you notice any such exclusions or if you think any of my edition sizes or release dates are off because those may not be entirely correct.
Darth Vader
+ Holo version (2500, AFX)
Clone (RotS)
+ Utapau version (1500, AFX)
+ Shocktrooper version (1500, SDCC)
+ 501st version (1500, SDCC)
Boba Fett
+ Holiday Special version (2000, EE)
Yoda
Greedo
Han Solo
Stormtrooper
+ Shadow version (1000, AFX)
Gamorrean Guard
Jawa
Obi-Wan
+ Spirit version - April '08 (AFX exclusive?)
Leia - May '08
Chewbacca - May '08
Tusken Raider - July '08
Luke - July '08
C-3PO - July '08
Emperor - Oct. '08
Jango Fett - Oct. '08
Bossk - Nov. '08
4-LOM - Nov. '08
Darth Maul - Nov. '08
Vader w/TIE
Luke w/X-wing - May '08
Han w/Tauntaun - Oct. '08
Clone Wars: - Nov. '08
Anakin
Obi-Wan
Grievous
Asajj Ventress
Ahsoka
Captain Rex
Battle Droid
Blue Harvest:
Darth Stewie
Chewbrian
Quag-3PO
Bobble Banks:
Boba Fett
Vader - '08
Yoda - '08
Stormtrooper - '08