I've rolled an Ubuntu 14.10 / Linaro 15.01 "developer" image for the Raspberry Pi 2.
Key points here are that it's compiled for ARMv7 and ARMHF, so should be faster than the Raspbian image by some amount. And it'll have more recent versions of software because that version of Ubuntu is significantly newer than Debian Wheezy!
I don't have anywhere good to host the image, so it's only available by bittorrent on my limited ADSL upstream, but once a few people are on that it'll speed up the download.
This is a pretty basic image -- it doesn't have a desktop environment installed for instance -- but it's otherwise working fine.
New version available: See latest blog post for details.
Another new version: http://blog.dryft.net/2015/02/2015-02-16-raspberry-ubuntu-release.html