As far as the special edition, a CD/DVD would follow the format of the last two albums. As for the questions about pre-orders, sometimes different retailers have different pre-order bonus tracks. For example, Depeche Mode's last album had 2 Best Buy pre-order bonus tracks, 1 iTunes pre-order track and some region only exclusive tracks. In addition, there were bonus tracks available without a pre-order. All in all, there were quite a few digital only tracks. Quite a few other bands have done similar. MTM had bonus tracks on iTunes, Best Buy and Walmart. What sucks is that half the time, it's live or remix tracks (the Depeche Mode tracks were ALL remixes).
I'm gonna wait until we get more details, but I'm sure I'll get the special edition, especially if the packaging is as cool as the MTM book.