Sheik is female.
This is what I've gathered....correct me if I'm wrong please.
Up smash-A definite kill more regaurdless of if it hits where the hands meet or not.
Forward-Much better and more useful than in Melee.
Forward- F-tilt combos were king in Melee for her, well, the F-tilt seems to have more knockback now. You can still combo them until about 50% or so (I think) but they can DI out of it, it's been buffed as a single hit, more difficult to combo with at high percentages since DI'ing is so influential now.
Aerials:
Forward- Worthless. It has minimal knockback now.
Up- Has multiple hits, can kill at approaching the 150%.
Down-A spike, but not nearly as useful as it sounds, since it causes her to plummet quickly and has a lot of lag when you hit the ground)
Needles-Nerfed. If you're charging them in the air, there's lag when you hit the ground still charging. I think they have a bit more power to them, but you don't hold the button anymore, it's like Samus' shot, you push it once and then again to fire. =(
Up B-Less lag, more powerful.
Down B-Takes much longer than in Melee, can't really be used for recovery it appears. Zelda is much more powerful now though.
Chain-Far more useful since it can now tether recover it has less lag.
Her dash attack is slower and doesn't look to be as good as Melee's.
She won't be top tier again...just watch a Sheik vs. Marth video. Sheik has a much rougher time than in Melee.