That zipzo threadI don't think it's hinting at Young Link if Toon Link can use the Fire Arrows considering he could already use it in Wind Waker (Unlike Young Link in Ocarina of Time actually).
Btw where did you hear/see that though?
Yeah it could possibly indicate nothing but the way I see it...
If every character gets 8 alt costumes and toon link only has six right now, that cold suggest a couple were left out or are unlockable.
Fire Arrow, Dr. Mario returning, it could all be adding up.