With the advent of PHP 5, I think it is less compelling to switch to a 
new languague because the  new object oriented robustness make it better 
suited for the modular design we could all benefit from.  I think PHP 5 
can hold its own on the command line, but the only only place it might 
be ill suited is the real time configuration as you have said.  Maybe a 
lightweight C program can handle the very basics, communicating with the 
other tiers of PHP?