I can, I'm not sure you will understand my interpretation though. When I A/B'd the PSB and Axiom speakers I noticed it most with cymbal crashes and acoustic guitar plucking. When I listened through the PSB's first I was very impressed. I next listened to the same passage through the axioms and was astonished. The crashes and strings sounded a small bit (but noticeable to my ears) "clearer." I used Dave Matthews, Melissa Etheridge, and Jack Johnson for those tests and I could always pick out the difference. I had my bro and dad stand backwards in the dark not knowing which speakers were playing and they came to the same conclusion that speaker B (the Axiom) sounded a bit cleaner.
Therefore the PSB's seemed to add a "warmth" to them that the Axiom's did not.

I wouldn't call the PSB's laid back or the Axiom's forward (who the hell knows what that means anyways?) just that the Axioms sounded a little more revealing for lack of a better term.

I've read some reviews that the new PSB's are more refined. I take it to mean that the presentation is smoother. Meaning if the reviewer thought the presentation was congested it may be a little less, or if he thought it was bright, it was less piercing. I would take the refinement with a grain of salt as I have not had a chance to audition them yet (that is coming this summer) myself.

I posted my thoughts somewhere about 7-8 months ago if you enter my name and "PSB vs. Axiom" I'm sure you'll find my more in depth findings there.