From experience on Sat night (in a club, mainly filled with 18-25 age bracket) the current chart stuff actually isn't going down too well with only a few exceptions - namely Cee-lo Green, Katy Perry (but not ET) and Rihanna - and the majority has a very short shelf life (measured in 1-2 weeks). I've been finding a lot of "Chart" from the last 6 months still goes down better than some of the current (Wretch32 for example).
From my own experience of 30th birthday parties, while people may ask for "modern" music or "current", they will rarely dance to it. Secretly they're all just waiting for someone to play "Love Shack", "Come on Eileen" or "Red Red Wine". I reckon it's like a mini mid-life crisis, 30 somethings just want to be seen as young and trendy, but are really just there for a bit of Dad dancing :D
I include myself in the above by the way... :o
Julian

