A proposed technical report by Unicode, the organization responsible for emoji, outlines plans to add a diverse range of five skin tones to the images as well as emoji that depict same-sex couples by mid-2015. The report itself is still a draft and includes the following statement about its status.
This is a proposed draft document which may be updated, replaced, or superseded by other documents at any time. Publication does not imply endorsement by the Unicode Consortium. This is not a stable document; it is inappropriate to cite this document as other than a work in progress.
While the report has not been officially adopted, it does show that Unicode is working to broaden the diversity of their emoji images. The recent update to Version 7.0 of the Unicode Standard added more than 250 new emoji.
image via Slate