I'm definitely aware of Pathfinder; I'm in a Pathfinder
(tabletop RPG) game right now. As I do with a lot of d20
stuff, I'm going to cherry-pick what I like from lots of
different sources -- Pathfinder, Trailblazer, Fantasycraft,
3.5, 3.0, etc. -- open licenses are wonderful like that. I
own the books and frequently check
d20pfsrd.com besides.
Incursion will ultimately be its own system and have its
own SRD, which I plan to make useable for tabletop play as
well as the roguelike game, with differences to accommodate
the different needs of each. Pathfinder fixed a lot of
things that were broken in 3.5, but it also broke several
new things, and there's a whole tabletop RPG balance
discussion there that I probably shouldn't go into here.
Some things I probably will take from Pathfinder include
sorcerer bloodlines, CMB/CMD, some OGL monsters, changes to
several classes, new OGL spells and feats, etc. You might
see versions of some Pathfinder classes -- the Oracle, Witch,
etc. -- in a new version of Incursion whenever it comes out.
But it's not going to hew to the system overall because it
has its own instead. Notably, racial attribute bonuses will
work quite differently in Incursion than they do in
Pathfinder. Incursion races are more powerful than any other
d20 system base races without Level Adjustment to my
knowledge, so they need their own standards.