> It's an upgrade in terms of compile times, deployment simplicity, conciseness, 
   > concurrency, etc. Some people care about such things.

I remember the days of going for coffee while the compiler chugged away but I wonder what compiles people do on a regular basis that take such time? I just rebuilt SBCL here on a mid-2012 MBP and it took less than 6 wallclock minutes in the background including download and whatever else I was doing:

   real	 5m12.752s
   user	 4m33.393s
   sys	 0m27.579s

I personally use D when possible, but waiting on compiles is usually secondary to the amount of time I spend thinking or exploring.