I
love Javascript, but I think people who want to develop server-side or desktop apps with it might be better served by Lua. Lua has functions as first-class values like Javascript does, which allows you to approach problems similarly in both languages.
Lua has also already been in use as a server-side and desktop language for some time, and while the available toolkits pale in comparison to what's available, say, for Java, Python or Ruby, there are still more options than there are for Javascript right now. Lua is very fast; for most benchmarks at http://shootout.alioth.debian.org it's the fastest interpreted language.
Sorry this is doesn't exactly answer the question you're asking but I thought it might be worth mentioning as another possibility to consider.