Whether it be to solve a problem or to contribute in any way, the Xfce communities are a good place to get help or to share your ideas. You might also want to have a look at the communities of the different distributions which provide Xfce.
Almost all development and coordination work is taking place on the Xfce mailing lists. A summary of all lists is available at mail.xfce.org. There is also a user-specific list where you can ask questions and freely discuss about the desktop.
NOTE: In order to post to these lists, you must first subscribe.
If you have a problem that you cannot resolve, you might want to try asking a question in our IRC channel #xfce on irc.freenode.net. The channel has several active users. It is recommended that you consult the documentation about your problem before asking your question.
For users who prefer forums, the Xfce Forum is the place to be. Active contributors will be able to help you, but please do not use it for bug reports.
The Identi.ca Xfce channel is a place where we automatically post all release announcements. It is no surprise tho that most social networks like Facebook, Twitter and Google+ have Xfce places and pages.