So I just had my first hour in the Rift. Tried the following:
Demo Scene:
When I put the Rift on and saw the display I thought something was off.
Is this what everybody was so excited about in all these reaction videos?
A flat screen in front of your face that just moves with your head?
Until I clicked on Start. Suddenly the desk and everything popped up and I was totally blown away, it felt like I was sitting right there, positional tracking is also pretty awesome in this demo!
Tuscany:
Very beautiful. I was really amazed how the perception of size feels in VR.
The house and everything felt a little too large but that's probably up to my IPD settings which I'm fiddling around with currently. 69,5 according to the utility is a quite large it seems.
Anyway, those particles and butterflies! So good! Looking out of the windows and over the balcony was also an awesome feeling.
First time I moved around felt like I was hovering, but it wasn't a bad feeling at all.
I slowly began to ran faster and didn't get motion sick after about 20mins of goofing around in the demo, so I guess this is something?
Sightline The Chair:
It's funny how much better this felt after I put my hands on my legs like the body in the demo.
I got bored out by the consistent looking back and forth pretty quickly but the locations were very well done and when the room got smaller I really started to panic for a bit

Getting ported in space was so sick!
I have slight fear of heights and immediately grabbed my chair when there was nothing but my magic virtual chair was there, haha

Sooo amazing. Can't wait to try more space demos.
What struck me the most was the scene at the skyscraper scaffold, I was like "nope nope nope nope", then the scaffold began to move and finally collapsed... I think my buddy on Skype had a great time listening to me while this happened... xD
Miku Miku Dance Beach thingy:
Not particularly impressed by this one.
Despite having 200fps+ the headtracking was stuttering and moving the view with the mouse/controller was stuttering.
Looking at the characters was a bit uncanny but the most impressive aspect of this one.
I quit only after 5mins tho.
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Setup was easy, but I'm still not sure about IPD and everything. Also my lenses are already quite dirty after only 1h of use... I will resist the urge to clean them, doesn't feel good with all the posts about scratched lenses going around :/
E: Another hour in and I guess I'll stop for today. Headache. Still not sure about IPD but I did the measuring multiple times now (one eye closed, both open etc.) and always came up with ~69mm.