A DAW is a DAW - work flow comes into play really when it comes to choice.
These days all the more well known Vendors all pretty much do the same.
Its then down to what they come with FX/Synth wise, or Video & Scoring wise,
and Nuendo for post production etc.
Audio cards are what the sound quality is all about for budget/project studios.
Of course Pro Tools HD and the Radar systems are another matter.
Been using Cubase for years and feel like trying something new [Just Gas more than likely]
Pro-Tools 10 does look interesting, but i am holding back for the moment,
Digital Performer 8 for W7 PC is out soon, and i have always liked the idea with that.[Mac only up till now]
Great Midi & Video/Scoring side to it.
Enjoy your Pro Tools, be interesting to see how you get on with it Charic.