I have Ouendan 2 now. I was surprised at a couple of songs that are in the game that I actually recognized from before. There's a song on there which is from Eureka 7 (one of my favourite anime) and the last song is the Ending Song from (SPOILER)the Densha Otoko TV drama.
This is another game that uses the DS vibration cart, so it's cool to feel that working. Ouendan2 has all the improvements that EBA had over Ouendan, plus a couple more that I noticed.

The Ouendan series is my favourite 'new' series from the last few years. Love it.