OK, this is my overall impression from Day 1 (premature, but whatever):
Updated: Tonality: The M100s are darker, but not by a ton. Maybe the new ones are 2-3 (maybe 4, max, tops) shades brighter. They allow some more details to shine. Vocals sound really nice, more natural. The difference is 100% noticeable but honestly it won't stun you. But definitely brighter, but not drastically. It *can* get a little (too?) bright on on brighter recorded music, so that may be an issue for some of you. I noticed it on some jazz and electronic stuff today.It seeems to sound better generally on rock.
Overall: this is a really really good sounding headphone. If you're in the market for a V-Moda build with audiophile sound, this is it.It also has the added flexibility of wireless if you're OK with not having aptX or AAC. For *my* purposes though, I don't feel they're worth the $355 (including tax) asking price. I feel like the M100 is a more fun headphone (when I want that) for cheaper, and it sounds better with electronic and jazz. Honestly, I can get the equivalent performance the CF II has out of my ATH-m40x that cost me $80. The CF II vs ATH-m40x aren't *that* different and I honestly think the m40x have a slightly, more versatile tonality to them, with cleaner sound.
I think the M100s may be slightly easier to listen to as well, just because of the darker tonality. It's not that the M100s are better or worse, just different. I'd describe the new CF II as a diagonal upgrade.
Keep in mind: this is just Day 1 impressions, so my impressions may change as I listen to them more.