Ok wait how does Assaj Ventress survive the fall on Yavin 4?

The fall Ventress survived was nothing compared to Anakin's dive onto a moving vehicle during the AOTC speeder chase on Coruscant.

If he could survive that, Ventress could certainly survive her fall-especially if there was, say, a river at the bottom to cushion her landing when combined with her Force powers.

 

Right now she is believed dead in the EU by everyone except for Obi-wan, who is currently on a "damn fool idealistic crusade" to track her down in the comic series Obsession, where it is expected both she and Durge's fates will be wrapped up (though only one of them is expected to be killed [likely Durge] while the other will be "changed").

Ventress's timeline of appearances occurs as follows:

-3 Weeks ABG: Found by Dooku (Clone Wars Chapters 6 & 7)
-2.5 Months ABG: Fights Obi-wan on the moon of Naboo (Republic #51 & 52)
-3 Months ABG: Encounters Mace Windu (Jedi Mace Windu: Schism)
-4 Months ABG: Encounters Obi-wan once again (Republic #53)
-4 Months ABG: Fights Anakin (Clone Wars Chapters whatever)
-12 Months ABG: Plays a manipulative game with the political situation of Cestus against Obi-wan's efforts (The Cestus Deception)
-15 Months ABG: Captures Obi-wan on Jabiim (Republic #55, 58)
-16 Months ABG: Obi-wan escapes (Republic #60)
-30 Months ABG: (events of Jedi Trial and Dak Rendezvous)
-30 Months ABG: Encounters Obi-wan during the Rendili crisis while tracking Quinlan Vos. Tracks Vos back to Coruscant, but goes after Anakin since Obi-wan and Vos are inaccessible. She threatens Padme and Anakin (though incurring a scar on his face) defeats her, believing her dead. (Republic #69-71)
-31 Months ABG: Obi-wan, not believing Ventress dead, goes on a personal quest to track her down and bring her to justice. (Obsession)

 

If you have the individual issue, on the credits page on the inside cover, down towards the bottom should have a statement along the lines of "the events of this issue occur 3 months after the events of Attack of the Clones" or some such.

It was just collected in the same TPB volume as the Defense of Kamino, even though that occurs 2 months ABG.

The Ultimate AOTC & the Clone Wars Timeline

 

It'll be interesting to see if they even have Ventress in the new season (the whole point of her "false death" in the cartoon was to give people who only watched the cartoon some closure on her character).

According to the VIPs on TOS, the new season of the cartoon will weave in and out of the events of several books and comics (Jedi Trial, Obsession, Labyrinth of Evil, etc) though, so maybe we will see her again- but unless they are going to adapt what is likely the conclusion of the Obsession comic series into one of the cartoon episodes (which I don't think is very likely), then we probably won't see her again because it would leave the "TV people" hanging regarding Ventress.

I wouldn't be surprised to see Durge again though, since he was always meant to survive his "splatter".

 

I don't reall Ventress being involved in Escape From Dagu- just another Dark Jedi we never heard of again.

 

Another possibility: Anakin reports about what happens, which finds it's way to Palpatine, who passes the location of Yavin IV onto Dooku to retrieve her.

Another: The flight log from Ventress's ship is accessed by Palpatine/Dooku agents, which is then used to find Yavin IV, and so on.