This is actually a pretty big realization for me. Between the documentation thread 2 months ago (http://arclanguage.org/item?id=12860) and this realization that the queue bug is all the fault of our arc implementation, my opinion of the racket runtime is entirely rehabilitated. (http://arclanguage.org/item?id=12302 was the closest thing to a flame war I've been involved in here)
Now my only complaint with mzscheme in general is that it isn't dynamic enough, and forces us to use its module system :) But even that's just because we're using racket in this weird 'backwards compatibility' mode. I'm looking forward to ar because it'll let arc use all of racket's modern goodies (keyword args, extensible equality, ...)
Edit: I suppose we're still stuck with scheme's phase-separated macros.
