I'm fairly confident this will be nothing like Shift. I'm also fairly confident this will not be arcadey.
I think the only way either of those 2 things happen is if they run out of money and need one of the big publishers to chip in. If that happens, I can see a them getting their hands all over it and ruining it like EA did with Shift.
I downloaded and played the latest release last night and while the physics aren't quite there yet, I think they're already much better than Shift 2's at this point. I don't feel like I'm floating over the track.
They released an unfinished Nordschleife and I have to say so far I'm pretty impressed. I don't know if it will best GT5's version, but it's a metric fuckton better than Forza's already.
Based on what I've experienced so far, this will be a day 1 buy for me.