What you can expect:
Four enormous levels, plus one somewhat smaller one. Not quite Descent 1.5 or Call of Charon quality, but surprisingly close.
Custom loading screens for each level.
Briefings, (at least if I can hack them together), exploring a part of Descent's overall story arc you might not expect.
Six or seven new music tracks. One for the briefings, one for each level, and possibly one for the title screen. For those who don't know, I've been learning the guitar over the last several years, so you can expect something closer to the Descent 2 Redbook than, say, my previous IDM-elecropunk sorta tracks for The Enemy Within.
Speaking of that estimable Enemy Within, guess which robots you'll face here? Hint: they're not the standard ones, and if you're not familiar with The Enemy Within you might be in for some nasty surprises on the last couple maps. If you are familiar with The Enemy Within, you still might find a couple surprises.
Lots and lots of neat D2X-XL stuff. All of the maps are at least set up with ambient sounds, and some of them have got more effects and even a little 'scripting' going on.
A massive battle to end the whole thing off.
=========================================================================
FNYABEFUQ (frequently not-yet-asked but easily foreseeable and useful questions)
Will there be a version of these maps for non-XL players?
Unfortunately not, these maps are enormous and many of them use XL features in ways that are pretty integral to how you play them. Plus, even if it were possible to "scale them down", I wouldn't have the time. And yes, I'm very aware that this limits how many people get to play these maps.
I know you like to use lyrics in your music sometimes. Will you insist on defiling my ears with this madness yet again?
Mwahahahahahaa
I've tried to use songs of mine that will reflect the main character's personality and state of mind as well as the level environments, in order to keep briefings a little bit shorter. Don't worry if you've got sensitive ears, though, at least there won't be any swearing 
What exactly did you do to the TEW bots for those "surprises"?
Weapons, behaviours, and models will all be as you remember if you've played TEW. Aside for a couple of minor retextures to fit slightly weirder level themes, there's only.... but I won't spoil that. Also, the bosses and the thief will use, mostly, their stock D2 versions.
When screenies?
I will try to get some screenshots up here in the next few days.
