Discussion of vertebrate and general anatomy issues are posted to the obo-anatomy list:
Support (for issues) and feature requests for the NCBO BioPortal can be submitted through the following venues (according to Benjamin Dai, BioPortal Lead Software Architect):
NCBO BioPortal User Group:
We are a (voting) member of the BioPortal User Group. The group has monthly teleconferences where new features are being discusses and subsequently prioritized through survey-voting.