This is an interesting (at least to me) discussion about the Reactor death in 3ds Max 2012.
Two thinks are clear (for now) - 1. the Reactor is riped and never will be back in the next Max releases, and 2. No any sensible reason for this decision until there is no equivalent replacement feature. If there was good reason, we will have an official explanation as well.
It's not just about Reactor, other features removed too, and as we know this is not the part of the legacy Autodesk politics, and this new course open many doubts and misgivings.