Will there ever be virtual surround sound for headsets?

To answer your last question first, the "Stereo Headset Adapter" will work with most surround sound headsets. The adapter itself isn't "stereo" it's just an adapter for the "stereo headset" which is where the stereo part comes from. With other surround sound
headsets, it's technically just a chat adapter, nothing more, because you're not electing to get game sound through the adapter, you're getting it through your existing surround headset.

For more information on which headsets are not compatible (there are only a couple I know of) check here:

support.xbox.com/.../connect-compatible-headset

A caveat - the part that shows an image of the old chat headset "puck" which says headsets that use that are not compatible isn't entirely true. I actually have mine working fine with that cable, but there are also standard 3.5mm to 2.5mm CTIA cables which
will also work in place of that particular cable.

As for your question about the Stereo Adapter using some sort of virtual or emulated surround sound, I highly doubt that the internals of the stereo headset would be able to produce that, but I can't speak with any certainty as to the future capabilities
of the headset itself, and really, the Xbox Staff would be the only ones who can answer that definitively (which I doubt they are allowed to do, as this would amount to an "announcement" of future plans.)

Hope this, at least in part, helps!

Adding on to Smiling Cat if you wanted surround sound in the future and don't mind virtual surround sound then you could get the DSS2 and use it with your current headset.

I've also been looking around trying to find a decent headset to buy and i think i'm gonna just go with the turtle beach x12 and then get the DSS processor to give it virtual surround.

Apparently reading up on it most people say virtual surround sound is much better on a headset than true surround because with true SS each ear cup has 4 little speakers in it which obviously having 4 tiny speakers produces a lot less quality than 1 big
speaker, what they make up for in surround sound they lack in actual quality.

So in the end it is better to just get a good pair of stereo headphones and then use a virtual surround sound processor if you want it.

It all depends on what you want the headset for and if you want the absolute best money can buy, as for me i'm only really going to use a headset for casual use on the night so i'm just going with the Turtle beach x12 as they seem to be quite good for the
price, but of course you can get a little better quality with a headset twice the price, but in all honesty its not that much of a difference.

That is a whole can of worms Many say that all headphones are 'fake' or virtial surround sound as you are not surrounded by 5 or 7 speakers, some headphone (I think) have 5 or 7 speakers but they are still all right beside you 2 ears so the effects are
questionable over 'virtual' surround sound.

Anyway, as far as I know the update (which I have) makes it so the optical cable can output surround sound...none of the new headsets for xbox one are connected using the optical cable. Your son's headset will connect by optical cable to the receiver/stand...so
for my money a headset like that will get you the best sound for now. There are rumours that surround sound might be possible at some point in the future through the adapter but I think that is a long way of and/or far fetched, I don't even know if it is
technically possible.

While some headset do use "virtual surround sound" to achieve the effect higher end ones do process multiple speakers in the ear pieces. But having such small speakers in each ear pieces, a true 5.1 or 7.1 speaker setup will always sound better.