Now I'm changing to two Kontrol X1, audio 8 dj soundcard and a 4 channel mixer. I really can't wait to use them with the new Traktor Pro 2 software.
(Pics courtesy of Skratchworx)
Skratchworx made an excellent review about the X1 (http://skratchworx.com/reviews/kontrol_x1.php)
I find it very intuitive to use and very fun.