uchoo786
Are the House bios etc. for the game considered canon?
Brandon Sanderson
Short version: no.
Long version: Crafty needs too much new material for their games for me to provide. I'd be spending hours and hours on backstory, and none on writing new books. We tried, at first, to make it all canon, but it was too time consuming. We do look it over, and try to catch any big errors, but the problem is that if I want to write more stories in Mistborn, I can't be bound by what the games have included.
That said, I'm mostly worried about extrapolations of the magic in this regard. (They need to be able to include powers and abilities that are good for gameplay, for example, and need to let people use metals in ways that the stories haven't explored yet.) I highly doubt there would be any reason at all to contradict the information about the houses and their bios, which looks solid to me, and in no need of revision.
So it's more of a "Yes, you can treat this as canon, but know that in some extreme cases it's possible I'll rewrite it in fiction."