Well he did seem to love the physics, don't know why he's being all Einstein towards it now
Sonic's movement reminded me a lot of Sonic Colors'. His jump is surprisingly shallow, making some platforming sections that should have been easy actually rather tricky. Also, rolling into a ball and hitting a spring doesn't carry inertia like it used to – running into said spring and staying on your feet to run up walls is the way to get up them.
You know, this is just wishful thinking but I think he played an older build. I ended up being excited more after the gametrailers pre E3 video's because a lot of tweaks I saw in the physics. Sonic moves way more fluid, there is more inertia, sonic's jump is a bit more floaty (in a good way, closer to the classics) and last but not least, uncurling is gone(whoohoo)
Don't know if you've seen this yet but the fact they're still busy tweaking the game even now gets me really excited
[youtube:1n8fy217]ifChuJKKZQg[/youtube:1n8fy217]