On my desktop I moved from Ubuntu, to Mint, to LMDE and then to Crunchbang. I definitely preferred Mint's polish to Ubuntu but never really had any need to deal with the community side of things. I've found the #! community to be extremely friendly and helpful however, probably second only to giffgaff IMHO
You're doing debian and crunchbang a complete disservice by writing them off like that. Crunchbang is basically a base with xorg + alsa + openbox/xfce and a few lightweight every day apps (ie exactly what you end up with after following the beginners guide on arch). Arch is pretty easy to get the base down and pacman is easy to use, just like apt-get, also crunchbang is rolling release just like arch. If you want to chroot your own base install and go build from source with your own CFLAGs etc... your best bet is to go for gentoo (or if you've got time to burn and want to learn, LFS).
If you feel like you've gone as far as you can with ubuntu I'll echo edgley, you really cannot go wrong with arch. I personally run x86_64 arch (liquorix kernel because udev seems to have issues with the 2.6.39 kernel with ck's patches), the community is fantastic, theres a user maintained repo of bleeding edge unsupported to get your hands dirty with and learning linux is all about breaking it and fixing it again!
I'm not writing off Crunchbang or Debian. They both have their strong points, just like Arch. The fact that they have much shorter learning curves than Arch is my point. Without the beginners guide, a new Linux user would not be able to install and use Arch like they could with Debian and Crunch.
I am only writing off Linux Mint because the community. otherwise it too is a solid distro.
This is all opinions on which is "nerdier" and which is preferred.