If you have a Nexus 7 you’ll be able to try out Ubuntu on your device now. I tried yesterday and, unlike the OMG Ubuntu posting states, it’s not quite polished as yet. However, as far as you would know it’s just like running Ubuntu 12.10 on your Nexus 7.
I found that the onscreen keyboard was unresponsive at times but if you have a USB OTG cable you can plug in a keyboard and mouse which worked very well for me, I also used the zram option [see known issues] which helped with the occasional lockup I was having
As an early release this is looking pretty good and I will be following this with interest. What I will say is it’s by no means a daily driver to use on your Nexus 7 in place of a Jelly Bean ROM but its pretty cool to have a fully functioning install of Ubuntu on a touch screen, give it a go yourself if you are feeling adventurous just bear in mind that we take absolutely no responsibility if you manage to brick your device.
This was by far one of the easiest non-Android installs I have done on an Android phone, with the Ubuntu Nexus 7 Installer all you need to do is put your device into bootloader and connect it to your computer running Ubuntu, then run the Ubuntu Nexus 7 Installer. I just happened to have downloaded Ubuntu 12.10 .iso and had it running in Oracle VirtualBox so I used that and followed the installation instructions.
Bear in mind if your Nexus 7 bootloader is locked and you want to try this out you will have to backup all the data on your devices SDCard before unlocking the bootloader as it wipes the SDCard.
Known Issues: https://wiki.ubuntu.com/Nexus7/KnownIssues