To help everyone out who's still going throught the demo, here's some PS3 info on attacks that can help out. Most of the Special move info is from the video FlashBlade has been mentioning (thanks for keeping that up). It's worth watching it just to see how these are supposed to practically work too.
(Posting a lot of this from memory and a little research, call out something if you think it's wrong)
Special Moves
(unofficial names made on the fly; at least they look cool)
Fwd + Square = Parry (also in the air)
Fwd Fwd + Square = Launch
Fwd Fwd + Triangle = Dashing strike
360 Rotation + Triangle = Spinning Slash
X + Square = Evasion (optional direction)
Bk + Fwd + Square = Palm Strike
Bk + Fwd + Triangle = Blade Sweep
Ninja Run + Square = Quick Slash
Ninja Run + Triangle = Slide
Ninja Run + Triangle + Square/Triangle (Slide + Ground slam)
Jump + Triangle = Dive Kick
Some Combos (from GameFAQs)
unconfirmed for right now, will give all a try and update soon.
Square (repeatedly) = unlimited light attacks
Triangle (repeatedly) = unlimited heavy attacks
Triangle (delay) + Square + Triange = Sweep 'n' Strike
Triangle + Triangle + Square + Triangle
Triangle + Triangle + Triangle + Square + Triangle
Square + Triangle (delay) + Square + Triangle
Triangle + Square + Triangle
(there's one or two, or more jump combos off of launcher, I'll post those later when I can confirm them again)
Tips
-Don't forget that with blade mode, you have the option of using square(horizontal)/triangle(vertical) strikes instead of the analog stick. Although, I get the feeling that correct aiming with the analog will really come in handy later in the game.
-Unless you're looking to get S ranking in everything, you might try experimenting with Blade Mode. Sadistic as it is, cutting off limbs and leaving the torso to walk or crawl in agony is pretty cool.
-The most opportune time to use Blade mode is when you've got a stunned opponent. Once the attack slows down and the guy glows orange, start cutting.
-Triangle + Circle gives you a stylish finishing attempt on an enemy once he/it's stunned.
-Stealth-killing is mostly getting above or behind a cyborg or gekko and hitting the button prompt.