CAVEAT: Anything below is from memory and strictly my own personal opinion. It should not be taken as an official ENnies statement, etc....
In general, I'd rather not see anything that fragments the awards based on format. If something is a good supplement, why should it matter whether or not it was a PDF or a print product? About the only category that print products have an advantage in is 'Production Values'. Personally, I'd rather see more dual-format stuff, as I prefer hardcopy for reading and table-use, and PDF for game-prep and player handouts, etc.
Print on Demand doesn't disqualify something for the 'Electronic' category. AFAIC, the fact that you had Lulu print it for you is not terribly different than having Kinko's print it for you, or burning through a couple inkjet cartridges at home. As far as encouraging publishers to do POD, I don't think that that's our place, or that we'd have much influence over that anyway. Customers emailing the publisher, posting in forums, etc., will have far more influence over that.