Excerpts from Marc Heiler's message of Sat Jul 16 20:24:10 +0200 2011:
>   /nix/store/5rnfzla9kcx4mj5zdc7nlnv8na1najvg-firefox-3.5.4/
Don't know what to say. Usually you don't work with those paths. So
there is no reason to worry about them. That's why I've a hard time
understanding what you're doing. On the one hand you seem to know the
basics of nixos - on the other hand you're worrying about such small
details which don't matter in practice cause implementation is hidden
from user. You use KDE or use PATH in shell. And there you only type
"firefox" or click on an icon. So it looks like you never really tried
using it. Well - mainstream distros (ubuntu,debian,..) still work better
for some cases such as mono development. However the most important
applications are working well. If you want to be little less mainstream
nixos easily wins. From my point of view we can close this
discussion - cause I sayd what I had to say.

Marc Weber