Looks like the conversations that have been in every SSB since Melee do return in the Wii U Smash Bros. This time, though, the dialog is more mission-focused. One set references the fighters, one does not.
Of interesting note, it appears that these conversations can be triggered without Fox or Falco on stage.
I definitely recognize Mike West as Fox in the Wii U footage, which I did not really recognize in the 3DS version. ROB 64 seems to have the same voice actor from SFAs. I think Slippy's actor is female.
Interestingly, Krystal seems absent.