The Ubuntu Wine Team takes care of the Wine application in Ubuntu. This includes handling bugs, improving integration and exploring new possibilities. At the moment the only active developer is Scott Ritchie.

Other Wine related projects such as integration features in Gnome, Wine front-ends like winetricks, and interaction with Wine's AppDB will be considered as well.

If you'd like to help with Wine, here are some practical things you can do even if you're not a developer:

First, please take a look at the unanswered Wine questions on Ask Ubuntu: http://askubuntu.com/questions/tagged/wine

You can also subscribe yourself as an Answers contact for Wine in Launchpad: https://answers.launchpad.net/ubuntu/+source/wine/+answer-contact

You can also be notified of every new Wine bug report by subscribing to the packages at:
https://bugs.launchpad.net/ubuntu/+source/wine1.4/+subscribe
https://bugs.launchpad.net/ubuntu/+source/wine1.6/+subscribe
Most bugs can be filed and linked upstream and marked low priority. Ubuntu-specific ones are generally Medium or higher.

You can also read and post on the Wine forum at the Ubuntu Forums. Many, many users ask questions here. http://ubuntuforums.org/forumdisplay.php?f=313

You can also contribute upstream to Wine by supplying good bug reports and information on the AppDB at http://winehq.org - If you do this, be sure you're using either the Wine beta packages or the daily build packages from the Wine Team PPA.