The difference between DA and the two games you listed are that they were both developed for the Xbox and Xbox 360 and then ported to the PC. This has been built from the ground up as a PC game.
Hopefully they won't do a demo, but some kind of prologue chapter or alternative story. Not focused on the character you will create in the full game, but a different character. Hell, you could kill them off at the end an intergrate it into the main game somehow.
<+pihlopase> Jesus Saves
<@jbroome> pases to moses, SCOOOOORE