The sort of the smilies array in vars.php is slow and pointless. It's adding ~1.5% overhead to every page load on my stock install.
As far as I can tell, it just rearranges the array on the off chance that a) you happen to display the smilies in a row with (e.g.) wp-grins, and b) you actually care what order they appear in. That isn't most people, and it can be done in a plugin besides.
See also #213: even if smilies stay in the core, they don't need to be editable by adding functions to wp-config.php, especially when the result is a slower WordPress for everybody else.
