His Moves should all recieve a buff most noticably his smash attacks, no nerfs. Yoshi can now jump out of his shield. Yoshi's eggs will also be the color he is (for example, the Red Yoshi will have red spotted eggs and the Yellow Yoshi will have yellow spotted eggs).
Yoshi's Forward Tilt from Brawl will now be part of his Neutral Attack. Neutral Attack - Left Kick, then right kick, and then a tail swat.
The Forward Tilt from the original Super Smash Bros. and Melee returns - Yoshi kicks forward, it can be angled.
The Up Tilt from the original Super Smash Bros. returns - An upwards headbutt, has set upwards knockback. Great for setting up combos, and a very useful move if used correctly.
He has a new dash attack in which he performs a dashing kick, being similar to Fox's dash attack.
Yoshi can now eat items.
Yoshi can now use his tounge as a tether recovery to stick to the edge to help out his recovery.
Grabs should be faster, stronger, and have more range.
Neutral Special - Egg lay - This time Yoshi and the other characters can pick up and throw the character that is in the egg (the tounge should have more range).
Side Special - Egg Roll - Gains more horizontal distance in the air and can be used as a recovery (Like in Melee) and will not put Yoshi in a helpless state when he cancels it in midair. It now has more super armor so Yoshi won't flinch out of his egg when he is hit.
Up Special - Egg Throw - Can even be thrown behind him (like in the previous games) and gains more height and distance when used in the air than in Brawl to help out his recovery.
Down Special - Yoshi Bomb/Ground Pound - It should be more powerful.
Final Smash - Super Dragon - Same.