Yeah the guys in the Pro Tools forums, some are freaking out, but the guy who runs the site, and is a hugely respected PT expert, is *not* freaked out as well.
One funny post said "all these 'pros' freaking out how the new Mac Pro is not a true Pro machine...also think the Macbook Pro is..."
The interesting thing for me now, just having played with a rMBP in the store, is that by the time the new Mac Pro is out, so will a new rMBP. I need both a lighter laptop (I have a mid-2010 15" MBP) and a pro machine for Pro Tools, Creative Suite, Lightroom, etc.
If money grew on trees, I'd max out a Macbook Air for on-the-go, and then go with a Mac Pro for the professional apps. The current rMBP machine, using all flash memory, is super-fast. I just ran Logic Pro, Aperture using 35MB RAW files, and Photoshop CS6 at the Apple Store. All ran blazingly fast. I'm sure they'll run faster on a new Mac Pro, but bottom line is that the performance was more than acceptable for me, and miles ahead of my 2010 MBP.
If a new rMBP (slated to come out some time in the next few months) uses the powerful and energy-efficient Haswell chips, along with the new, faster PCIe SSD flash memory first implemented the just-updated Macbook Airs, I may just opt to max out a mid/late 2013 rMBP for both portable and home use. The move to all-flash-based HD gives me confidence to take that machine anywhere/everywhere, with no moving parts to fail. The retina display is awesome to look at, and I could be confident that a maxed out rMBP would be more than sufficient to run all my Pro apps very well.