yeah
just like Vinyl has been all of this time, CDJ’s will still be here for a long time yet.
Firstly (just like vinyl) there will always be some DJ’s who claim they can hear a sound difference and want to DJ only from CD, not even well ripped, high quality MP3’s. What they will fail to realise (just like vinyl) is that very few sound systems are good enough, and well set up enough, that the difference is noticeable, and even if they have well tuned, practised ears that can hear the difference the crowd don’t, and wouldn’t give a f**K anyway even if they did long as they can dance along and sing the words if there are any they will happily put up with some shocking quality sound systems and music. But they’ll be a loud enough minority to be heard and keep CD’s going.
And secondly the wonderful, and at the same time limiting, factor of all of this amazing equipment is that its so customisable, and as people have said this means that everyone has their own set-ups, own controllers, own midi maps etc etc and there will almost certainly not ever be a “standard” layout.
Thirdly while what’ll probably become standard is using the midi/hid functionality of most CD decks nowadays, set up with USB cables so people can use them, they’ll never take the CD part away as a back up. It acts as a great backup in case someone’s laptop goes tits up (I always carry enough CD’s, and keep them up to date, that I could get through a night without them and not totally suck should the worst come to the worst) and also the bar staff in the club/bar wont have laptops all set up for DJing so when they’re in setting up before the DJ arrives, and cleaning after, they’ll want something to play some CD’s through. Particularly again if its a bar they’ll want background music for during the day etc.
More space will be designed in though, extra stands and shelves etc, to accommodate all the new gear, and they’ll build extra connections into panels on the wall or somewhere next to the decks to make it easy to add extra inputs in from sound cards etc without having to root in about the back of the mixer messing with system cables.
The other thing about this kind of thing is that I don’t think people would trust an installed PC/Mac either. Partly because you wouldn’t know who had been messing with it and whether it was stable or will crash, or if your gonna plug a memory stick in and catch some other DJ’s computer virus and take it home into your own systems as an extra wee surprise. It would need to have both Serato and Traktor plus some hardware to go with it and will venues want to pay for all that. and every time you went in you’d have to spend a whole heap of time changing the screen layout from the last guy, adding in your settings and mappings and collection etc etc.
Much easier to rock up with your own lappy, all set up the way you want and clean and maintained so you know it wont crash or fail on you, and whack two or three cables in and your done 
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