Who is the Neimoidian in Star Wars Clone Wars the animated series
"Neimoidian Guy" has never been named.

In the preview for Legacy #5 it says that Darth Nihilus retains his consciousness in his armor, (I'm assuming his mask). Did he do this before or after his suposed death at the hands of the Jedi Exile?
For now, consider it a mystery.

Are the Ewok films considered G-canon since Lucas wrote the story for and executive produced both of them?
I don't have documentation detailing exactly which parts came directly from George, so I still consider it C-canon.

In which system was Outpost D-34 located?

In the preview for Legacy #5 it says that Darth Nihilus retains his consciousness in his armor, (I'm assuming his mask). Did he do this before or after his suposed death at the hands of the Jedi Exile?

What era is Darth Andeddu from?
Hasn't been specified.

Who captured Tydirium first
A combined effort, though "Ace" Azzameen is the first one on the scene.

Star Wars: Demolition endings are canoninical?
Canonical endings have never been determined.

I would still like to know - Who captured Tydirium first, and which of the Star Wars: Demolition endings are canoninical?

*should we assume anything in Galaxies itself that doesn't appear in the strategy guides and websites (if anything) would be treated in the same take-it-or-leave-it fashion as S-canon materials?*
No, still C-canon, it's just less likely to be referenced. I can always contact the Galaxies development tean should I need to confirm anything in the game.

During the Rebellion era, do Luke and Leia have separate birthdays? Will a future source shed light on this?
Nothing currently in the works.

Why do some Kiffar have yellow marks, (e.g. Quinlan Vos) and others have black marks, (e.g. Ailyn Vel)? Is it because they're from different clans?
The comics have plenty of Kiffar (Maritan Kas, Horsea) with different color marks. The Tonnika sisters who are supposed to be from Kiffex have no marks at all.

the Handmaiden's and Hanharr's backstory .... Are the backstories themselves still canon, though, even if the character can't canonically learn them?
Yes.

Some of the other questions I've addressed in my blogs.

Thats true Hedec....but why pick Ruusan to begin with? If I had a chance to write a book about Palpatine, why would I pick the time during +Revenge of the Sith+? The story has already been told and all I'm going to do is make things worse by adding on and changing things.

Yes we can all Retcon the events in our own little minds, but really dont you think it would have made more sense to write a completely brand new story? I guess it's not a really big deal.

*It's not that it's more "Canon" (note spelling), *

thanks for the help

Just added a blog entry that breaks down the parallel scenes between POD and JvS for those curious:

Excellent!

In fact, the reason for the HolonetNews story on his speeder accident and subsequent facial reconstruction was to explain this vastly different appearance.

And yet he looks like he did in TPM in ROTS.

+
Is the deep-voiced Nemoidian on Geonoisis really Rune Haako? Because that contradicts the films. +

Not really. His name is not mentioned anywhere in the film. In fact, the reason for the HolonetNews story on his speeder accident and subsequent facial reconstruction was to explain this vastly different appearance.

Still say he should be Gilramos Libkath though...