It seems a little early to be making any committed switches. I think I'd wait until after I built something significant before I announced that something new was better than something old. Especially when betting on a combination of new tech such as Go and NaCl.

Most of the reasoning here that's not flat out wrong (such as to the reference to lack of Google support for Python, inability to secure the platform, ), seems performance focused, so perhaps that's a sufficient justification?