Just Dance 4

Definitely, "Part of Me" by Katy Perry has been confirmed. What song do you expect to have as Downloadable Song/Alternate Routine?

For the song:
*At least one song from Backstreet Boys
*Famous - Big Time Rush (Duet Mode, Male-Female) (or at least one from from this band)
*Jet Lag - Simple Plan
*Macarena - Los del Rio (Duet Mode, Female-Male)
*Oppa Gangnam Style - Psy
*Y. M. C. A - Village People (Crew Mode)

For the alternate Routine:
*At least two songs in Hold My Hand Version
*Hit 'Em Up Style (Oops!) - Blu Cantrell (Alternate or Extreme)
*Mas Que Nada - Sergio Mendes feat. The Black Eyed Peas (Alternate Male Version)

I'd see some songs from JD3 available as DLC for JD4.

I'll name three songs from the top of my head (Two for all systems, one for just the Wii U):
*Spectronizer - Sentai Express
*Pump It - Black Eyed Peas
*Just Mario - Ubisoft Meets Nintendo (Wii U version only please)

Also, has it been confirmed that the PS3 version of JD4 will get DLC this time since its version of JD3 didn't get any DLC?

[This message was deleted at the request of the original poster]

Well, forgot my first post......
Anyway, "Gangnam Style" was also confirmed by Ubisoft and it will be released in November. Here are my new prediction:

SONG:
-At least one song from Backstreet Boys
-At least one song from Big Time Rush
-At least one song from Michael Learns to Rock (Maybe Sleeping Child or The Actor)
-Butterfly - Aqua; Duet; Samurai(Male)/Geisha(Female) or Vice Versa (Song can be the Cover Version)
-Macarena - Los del Rio; Duet; Female/Male
-September - Earth, Wind & Fire (or "The Groove Century")
-We Like to Party - Vengaboys (Maybe)
-Y. M. C. A. - Village People; Crew Mode (Song can be the Cover Version)

ALTERNATE ROUTINE:
-At least one song each in Hold My Hand and Line Dance
-Mas Que Nada - Sergio Mendes feat. The Black Eyed Peas; Alternate Male
-Never Gonna Give You Up - Rick Astley; Alternate Difficulty 3 or Extreme