Update: this project is abandoned, the repository is left for achælogical purposes.
Our goal is to create an OpenType MATH-enabled font euler.otf, by combining the existing Euler math fonts with new glyphs from Hermann Zapf and adding MATH table information.
The MATH table work is almost done, and initial glyph review by Zapf have been conducted and implemented, see http://tug.org/TUGboat/Articles/tb29-2/tb92hagen-euler.pdf and http://river-valley.tv/reshaping-euler-a-collaboration-with-hermann-zapf/ for more details about the review process. We are planning for another review before the first official beta.