The good news for DP users on both sides of the platform divide is that DP8 is 64 bits. I use many third party plugins so once DP8 is available and makes use of 64bit memory addressing I'll be right on top of it.
I use DP7, PT9 and Logic 9. More than once when someone who isn't familiar with Logic, usually someone who uses Pro Tools because it's the industry "standard", sees Logic for the first time I get a comment that it "looks like Garageband".
If I need to migrate a PT project into DP or Logic, and give people a choice, DP is usually perceived as "a serious app" and Logic is more "eye candy", even though Logic is very CPU efficient and has some excellent bundled plugins.
And that bring me to my next point: Logic may go the way of FCP-X and get dumbed down to the point that serious end users will move to more "pro" apps even if they cost more, leaving the Logic-X users as the "prosumers" as far as the industry is concerned. For the solo artist it will be great, cheap yet powerful, and easy to use. Apple will sell a lot of Logic-X apps.
Pro Tools users will get routinely $hafted by Digi.. uh.. Avid, and have to deal with artificial limitations built into the software, yet another proprietary plugin format, and hardware that is expensive and obsolete in no time. Sure you can use Pro Tools now with third party interfaces, but anyone who has tried has run into built-in roadblocks that are another topic entirely.
So DP could come out ahead in a way, not in total sales to the masses , but in gaining more traction in the pro world. We'll see. And hell no, I'm not buying a PC!