uClibc has a mailing list for discussion and development. You can subscribe by visiting this page. There is also an online archive. Only subscribers to the uClibc mailing list are allowed to post to this list.
There is also a mailing list for svn commits for people wishing to read the complete diff of each and every change to uClibc -- not for the faint of heart. Active developers can subscribe by visiting this page. The Subversion server is the only one permtted to post to this list. And yes, this list name uses the word 'cvs' even though we don't use that anymore ...