Herd 5 is due on March 1, and the Xubuntu Testing team needs help. If you have a spare machine and an hour or two of your time, they need as much input as they can get to make the date. From the xubuntu-users mailing list:
We are preparing to release the fifth alpha (Herd) release of Xubuntu Feisty Fawn on March 1st, and we need your help in testing our current nightly builds to meet this goal. …
::Important:: If we don’t report our results, we won’t release an offical Herd 5 release. So if you test, make sure you report it!
So as I read it, you don’t have to be an Ubuntu member to help out. And you get all the fame and glory that comes with being a valued member of the community. You can put it in your sig on the forums! :D