Wow, this game sure has come a long way since we last saw it! It definitely has a Battlefield vibe to it. I was also reminded of Twisted Metal: Black Online, particularly with a few portions of the video demonstrating the ground vehicles.
Even if it isn't officially confirmed as a downloadable game, I wouldn't be surprised to see them go that route. After all, if it's going to be only playable as an online multiplayer game, then they might as well distribute it online. Also, this would eliminate confusion at retail for people who purchase the game and expect there to be some offline single-player component.
If offered as a downloadable game, this (along with other games like Tekken 5: Dark Resurrection) could serve to call attention to the download system, and pave the way for digital distribution of major high-profile releases in the future.