I'm living in a communal house in Cincinnati with 2 German women, a PC-only gamer, and a community outreach organizer and I introduced them all to Nintendo Land tonight. Best night we've had yet - it beat out our favorite board games and launched itself into our new favorite thing to do together. It was a blast!
Afterward, we got some Just Dance 2 going while the PC gamer and I played League of Legends. It was a wonderful night and it's great to see people enjoying my Wii U so much.
The community outreach organizer even commented on how everyone she knew was making fun of the wii u when it came out and she's surprised that it's so much fun. I really hate the videogame industry sometimes and how vocally anti-Nintendo it is.
[edit] In conclusion, don't forget about Nintendo Land! It's a party for 5!
I would get Wii Party U also. It is a blast also. Not 5 player but 4 is still good.