It's very odd choice, especially when there is actually a push for more technical categories - such as projections - I wish they would have pulled down to best sound design (for both musicals and plays) . . . rather then eliminate that category at all.
I think there is a push to break out of the technical awards and have a smaller group (like the Oscars do) nominate them, and then maybe have teh whole group vote.
I think rather then dump the category, they should have spent time and effort to educate the voters on the importance of sound design.