Like Melee and Brawl before them, the upcoming Super Smash Bros. for Wii U and for Nintendo 3DS will feature past stages for players to fight on. In tonight's Smash-centric Nintendo Direct, Masahiro Sakurai displayed several stages between the two upcoming Super Smash Bros. titles before confirming that both versions will feature arenas from past games in the series.
The only two stages confirmed so far are Jungle Japes, which first appeared in Super Smash Bros. Melee, returned in Brawl, and comes back for round three in Super Smash Bros. for Nintendo 3DS; and Halberd, which appeared in Super Smash Bros. Brawl. Sakurai then made clear that Smash for Wii U and for Nintendo 3DS would not have the same past stages as each other.
If I had to guess, I'd say that stages from Melee and maybe even the first Super Smash Bros. will appear on Nintendo 3DS, and stages from Brawl will appear on Wii U. ...But it's also completely possible that there's no trend and I'm inferring way too much from just two stages.