According to Sandra Scoppettone's recent blog there will be no more mass market paperbacks published after 2007 or thereabouts. Everything will be hardcover or trade paperback.
I sure hope this is a wild rumor. It's hard for me to fathom a world without paperbacks as we know and love them. Granted, they're mighty expensive these days, but they're cheaper than tpbs or hcs, as we aficionados call them.
Do publishers really think people will spend two- to four times the cost of a pb for a book by a newcomer or non-bestselling author? Or are mass market pbs unprofitable these days, forcing this change? Beats me.
It would seem to me that if the major publishers did discontinue paperbacks there would be a huge void left and some enterprising newcomers would rush in to fill it. After all, paperbacks started in order to serve a need (cheap books for the common man/woman) and that need still exists despite the deplorable dearth of new readers spewed from the hallowed halls of modern learning.
I won't even go into the issues of shelf space and convenience that can only be satisfied by paperbacks. I'll just say that if there are no more new paperbacks to read I'll finally have an excuse to read all the old ones I've been stashing away for the past 20+ years.