I don't post very often on this board, but I do read it quite often. This topic is near and dear enough to my current situation to elicit a response, however...
I actually do teach electronic music classes (two levels) and I have always used DP in these classes. A couple of years ago, I added a couple of GarageBand assignments for the intro class because it's such an easy way to introduce sequencing, but the rest of that class and the entire advanced class is done with DP. I have personally used DP (and Performer) since '89 (first at North Texas--hey, Shooshie! I never knew I had a connection to you...), and would never dream of using anything else. I did have to teach a course at another school several years ago using a pre-Apple version of Logic, though, and it was such a bad experience, I never even considered using Logic again. Until Logic 8.
So, feeling like I should at least check it out, I ordered a copy of LE8 to see just how much it has improved. I spent this weekend doing just that. I must say that I am impressed with it's ease of use--especially for an overall beginner and especially compared to previous versions. For someone that knows DP quite well, of course, I have to relearn some things, but overall, it's pretty simple to pick up. For this reason alone, I
might consider switching to Logic Express for my electronic music classes, just because--after years of teaching it--DP is sometimes very difficult for students to learn (a lot of non-music majors take the intro class). Logic is so similar to GarageBand, it would be easy for students to make the transition.
I am, however, definitely going to wait to see what MOTU does with the next version of DP. Even then, I'm not convinced that I will necessarily switch my lab over at that point.
Students constantly ask my opinion about software and hardware. If I've used it thoroughly enough, I give them my honest opinion. I am always careful, however, not to throw around the "I'm an expert and here's the way things are" tone during these discussions (because I certainly don't know everything there is to know, that's for sure!). As I tell my students, different apps and hardware are good for different needs and you have to use what works for you and what you are comfortable using. I was NOT comfortable using Logic in the past, but now I am. I still doubt I will change my personal use of DP, however; I'm just too comfortable using it. For the same reason, we will probably continue to use ProTools in our studio recording classes, even though DP and Logic could certainly do the job there. Our ProTools instructors are just too comfortable using it to switch so quickly, if ever.
I do know one thing: I don't ever want my audio technology program to be a "one-app-does-it-all" program. I think it is in the students' best interest to see how various DAWs and other apps function so they can compare them for themselves. This ulitmately will help the students more, whether they eventually create their own studio and buy the gear themselves, or end up working for someone else and use whatever they have.
Sorry this is a bit long-winded. I just wanted one of the "superior professor types"
to express the opposite opinion: I would never tell my students that anything is "doomed." To me, that is beyond arrogance; it's silly at best and irresponsible to the students' education at worst.
(including professors! 
).