from what I have read in the past, it is much easier/quicker to do native support for HID devices like the cdj's, the 3700 is straight midi not HID so it is harder to get the spinning platter to work properly. I know companies software like Reflex has support for the platter but you see how popular that is

also Serato does not totally ignore Denon, it does have native support for some of their controllers. and if Denon announces support on the 16th in a hybrid mode kinda way, it proves once more that serato had difficulty get the midi platter to work perfect so they went the hybrid way and we all know serato is not going to release half assed support for the 3700, if they cant have it work perfect they wont release it otherwise people will trash Serato because denon didnt build their players with HID support
This is right from Seratos mouth (or fingers really) on their forum just to back what I said
I'm not sure whats up with all the speculation here - There is not secret agenda going on here, no conspiracy.
I thought I have been quite clear about why they are not supported but I'll recap:
Serato was not consulted or approached during the design process of the Denon 5500 and 3700 decks. The 3700 / 5500 decks have no touch sensitivity and spit out much lower resolution data than what we would require to support them properly. There are some tricky things we could do to try and work around this (read: technical hurdles) but the results are still pretty unsatisfactory. Either terrible warbling playback, or terrible sticker slip. Trust me, using the control signal on a USB stick will be much, much tighter.
I think it would reflect badly on both Denon and Serato if the products did not work together properly.
About ITCH? ITCH products are a collaborative process involving the hardware company and Serato from day one. We work on what data we get from the hardware and what the software needs when the product is in the design phase, not after the release. That is why, (in my opinion anyway) the VCI-300 and the NS7 are incredibly tight.
I hope that's relativity clear, like I said, no conspiracy here. Serato and Denon are on very good terms.