The semantic difference between process.nextTick and setTimeout seems negligible in this case (while it might not be for edge cases). I would therefore argue that compatibility is more important than Node conventions (especially considering that `renderComponentToString` is part of React's default distribution and not part of some server side add-on).

Anyhow, let's wait until the core team has made up their mind w.r.t. asynchronous rendering in general :-).