Aw, now I wish I hadn't gone and looked for this "Lotus video" you speak of. The game looks exactly the same...
...okay, so maybe "look" is the wrong word. Sure, the graphics are pretty and all, despite the lack of proper shadowing in the tunnel (the pillars don't show up on the car) and the fact that the "curtain of blurriness" still plagues the replay...but the car sounds exactly the same as in GT4, it seems to move almost exactly the same (I wish I could see a competent driver in a RWD with the TCS and SCS off), and from a crappy GameSpot video I saw, the cars crash the same way as they do in GT4.
I'd love to be able to chalk all of this up to unfinished, pre-release gameplay, but lately Polyphony Digital has given me no reason to give them the benefit of the doubt. I'm becoming a bit apprehensive of what GT5, or at the very least, GTHD, will have to offer other than graphics improvements.
C'mon, PD. Prove me wrong.