Some photos I rigged up quickly in paint(explaining the terrible quality) Personally, based on my small observations(paired with what Sakurai has already said), I'm inclined to say Ridley will NOT be playable.
Based on the way the shadow is, not only is Ridley's wingspan HUGE in regards to the stage, and especially in regards to pikachu. His wings and shadow go from the "center" where people actually walk, to the very end and off on the other side. This means that either he's not "centered" or he's flying the entire time. A mechanic unlikely to be implemented in smash. Even then, his shadow Is VERY large relative to other characters, and is even slightly bigger than the Yellow Devil's shadow from quick observations.
Along with that. I did this in like, 3 minutes, So I may draw up something better later. Anyway, just my thoughts. Take it as you will.
(Also notice that Pikachu does not have any shadow.)
http://s739.photobucket.com/user/Dragon1128/media/Ridleydeconfirmed_zpsca3efa73.png.html
http://s739.photobucket.com/user/Dragon1128/media/RidleyDeconfirmed2_zps88e41298.jpg.html