On December 25th, the log4net team released version 2.0.6. This release includes support for .Net Core version 1.3 and other bug fixes. To see the full release notes, go here.
The team is also looking for contributors. I had the opportunity to helped the team by submitting a patch for issue 527 https://issues.apache.org/jira/browse/LOG4NET-527. It was a minor fix but I know for sure that the log4net appreciates any help.
My hope is that more developers contribute back to this project and make it even better as we entered 2017.