2.Soundtracks
The Soundtracks in DJ Hero 2 are english songs that got published in the europe too, because the creator wanted to make it "euro-friendly". There are tracks for example:
1."Get busy" by sean paul
2."California love" by (forgot name)
3."Get ur freak on" by missy eliot
4."Acabella (extended david guetta version)" by kellis
and alot of more!

2.1. Downloadable content
You can download music at the music shop for (at the wii) 300 points. There are songs like:
1."house music" by benny benassi
2."shake & pop" by green velvet vs. "i'm in miami b*tch" by LMFAO
3."OMG" by Usher
and some songs by tiesto.

3.Change
Well...the control change are said already... then... DJ Hero got a career like mode called "Empire" where you can unlock DJ's like:
1.Dj Quebert
2.David Guetta
3.RZA
4.Deadmau5 (or how i call him mickey mouse xD)
5.Tiesto
and i think that's it.

At DJ Hero 2, there is a Quickmode, the Empire mode (just told you about it), a online mode and a party play mode.

3.1.1.Quickmode
You can choose which song you would like to play and... yeah... you play it.

3.1.2.Empire mode
I just said what it is before...

3.1.3.Online mode
Remember what i said about the online mode in DJ Hero 1? This time it's different. Now there is a really good chance that you find someone to play with. There isn't always someone there, but the most of the times. At the online mode, you can choose what you want to play like:
Dj Battle
Checkpoint
Power Deck Battle
and a lot of more.

3.1.4.Party play
At party play, you can play with 2 turntables and a microphone.

4.Sell
If you look at the sell of DJ Hero 1, you could see that DJ Hero 2 made almost 63% of how much DJ Hero was sold. Meanwhile, the Guitar Hero series got worse too, so activision decided to stop with DJ Hero and the Guitar Hero series (or atleast cancel all ideas of 2011)