One thing VirtualDJ does fine, was the "Intelligent Automix", one of different Playmodes to her Automix funktions. In that specially mode it plays the following song in the same BPM as the song before. After that, the BPM automaticly rises smoothly to his own real BPM and so on!
That was the first thing I wanna do in Traktor and readed, that this easy funktion don't exists!