My friend and I are playing through CotCT; my husband is DMing. This is the first time my friend (I'll call him Mork, because that's his character's name) has played D&D in about fifteen years.
So far, he's picked up everything very easily. He's playing a half-orc monk and really likes the range of abilities he has. He's a little reluctant to use ki points for fear of running out, but I think he's striking a good balance.
I, of course, have been playing 3.5 for a long time so I find the rules easy to adapt to. I love the more customized speciality wizards -- I'm playing an illusionist -- and the utility of the rogue (my second character) seems unchanged. I've always liked rogues.
The main issue Mork has is he keeps thinking "bull rush" should knock down your opponent. Something he'll figure out soon enough, I expect.
Will post more as we play more!
-Amber S.