Yes, I agree 100% and forgot to create a post about it here in 'feature suggestions' :
For the same reasons as Stuart, that feature, especially with the ability to automatically mix/crossfade/fade in & out (like Traktor does well) -otherwise the silences at the beginning and end of the song sound amateurish and ugly to our clients' ears who pay us substantial amount of money, so they deserve minimum quality !-, is extremely useful to generalist DJs. Indeed, they have to play continuous music for 8-12h00 which is not possible to do with sustainable top quality and in a healthy manner considering human physical and mental limits (fatigue hitting after a few hours) and the first part of their gigs usually doesn't require manual mixing by them, so an Auto Mix would be a great new feature in Rekordbox DJ (a typical example being that of a wedding party starting at 5pm with pre-dinner drinks followed by the meal & ending at 3-5am the next day, the manual mixing starting at 10pm with dance floor music).
I am currently, by technical obligation, with Serato SDJ and it has auto play but without mixing which embarrasses me a lot by its silences at the beginning/end of songs !
I hope Rekordbox DJ will have these basic yet very useful features in the very near future, thanks in advance.