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?
"A little early" seems like a giant understatement. Go has only been out for about a month. Python has been out for ~18 years, About 200 times longer than Go.
Why someone would choose to switch from a well established language to a brand new bleeding edge one is beyond me.
A calculated gamble on the new language becoming popular in the next several years?
It's like investing in a company; the smaller it is when you throw in your lot, the better placed you'll be when it grows big. Imagine that Go becomes the Next Big Thing five years from now, displacing large amounts of C/C++ code--this guy would then have five years of experience under his belt in the hot new language right as its popularity spikes.
The potential downside is that the language never takes off and you end up an expert in something that no one wants (see also: Lisp.).
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?