Bunsenlabs linux has been in development for about a year and was just released at the end of April. This was one of three prospective successors to Crunchbang Linux (the other two being Crunchbang++ and Crunchbang Monera). BunsenLabs took the longest by far to be released, but it seems to be the one that captured most of the Crunchbang forum users. It isn't substantially different from Crunchbang++, but there are a few noteworthy differences I have discovered so far. Like Crunchbang, BunsenLabs features a very customized version of the openbox window manager, as well as the tint2 taskbar and a conky display on the desktop. BunsenLabs is less sombre looking than Crunchbang, uses the latest Debian Jessie respositories, and has four customized application icons on the tint2 bar. Like Crunchbang, BunsenLabs offers clickable scripts to install non-free codecs and various applications.
BunsenLabs can run on a live USB; I don't think that any of the others have this feature. It runs well in live mode. Unfortunately, installation was a bit of a chore. I followed the distro's instructions for creating a live DVD, but couldn't get the installer to boot. Live USB did install, but it had problems, too. It didn't install the distro sources, and I had to do that by hand after the installation. But once that was done, all was well.
If you want more information or want to download the distro, check out their website: https://www.bunsenlabs.org.