There is such a thing called a "Cannon PC", these are typically the character's they use for there side material like comics or books. But, I think why this person is wanting to know is what class and race is this Inquisitior on the cover of the game and on posters and in the Trailer's. It would seem like it is a two-handed warrior though it could also be a sword and shield warrior(minus the shield, like they have tended to do with there NPC's in the series). The character from the DA:O trailers was in my opinon a Arcane warrior( which means they started out as a Mage). But with Awakening DLC and a little bit of looking into if he was truely Malcom Cousland then that character could have been a Templar/Spirit Warrior( hence the Blue Flaming eyes.) But, I don't really know, as for Hawke, from the trailor they did the "Hawke" was Garret Hawke/ Mage/ Fire, Ice, Spirit, and also a Blood Mage. Because when the Arishok cut him he took the blood and used that as the source of power to conjure up them giant hands to rip the Arishok in half. Also if you were paying attention "Cannon Hawke" looks to have had more than just a friendship with Isabella, as that was his source of needing to not fall to him in battle. As for the Inquisitor WARNING!!! Spoiler.......
When you finally get yourself settled in at Skyhold Cassandra and Leliana other you the Sword of the Inquistion and you take it to show everyone you accept the full responsibilities and will lead all those who followed you to Skyhold. Now it could just be me but a Female or heck even a Male Elf or Dwarf would take away the awesome feeling that scene gave me. Seeing as the sword is Half the size or either of those races. So then that leaves only two other classes left. But, if you play as a Male Qunari that sword looks like a dagger compared to your characters size. From all the trailers, posters, and a few demos. My best guess (and this is what this is) is it's either a Male Human Warrior (TH or SnS) or it is a female Qunari and as for what class I do not know.
So yeah, people only want to know what the canon is because either, they can't make up their minds on what they want there character to be....or they have already beaten the game at least twice and want to play the games in such a way that the follow all the little extra things have to offer ( primarily the books).
Y'all are more than happy to disagree with everything I have said but for the most part I tend to think most would agree with me. So all you people saying who cares, or there's no such thing....there is such a thing as a canon. The Dev's at least need a story to work with and then all the little things like race and class take care of themselves via ..US the players.