The primary release method will be as an upgrade to existing Descent customers - not a full pack, which purchasers of D1 already have. This will please the "player only" crowd. Full packs with both D1 and D2 will also be made available.
With the intention of releasing at Wakefield at the end of this month, and some of the features still not quite finished, multiplayer gaming will be missing from this release, but it is going to be worked on after the show. The game engine has been improved over D1 with transparency effects, bilinear filtering and multiple screen resolutions and colour depths; some improvements, such as a faster game engine, will filter back down to D1 owners too.
This certainly sounds like a step in the right direction - a player only purchase path (if you've bought the original version), commitment to networking games and yet more extra missions packs, it would appear that RCI have come up with a good value package for RISC OS 3D gamers.