Minor one, but potential for a bug. mod_php*.ebuild all have a variable assignment of APACHE2_MPM akin to this- APACHE2_MPM="`apache2 -l |egrep 'worker|perchild... This is a problem, since if the user sudo's, their path lacks /usr/sbin/ (so the entire assignment fails). This should be APACHE2_MPM=`/usr/sbin/apache2 -l |egrep 'worker|perchild...'
if the user does 'sudo su' and then an emerge, there is a LOT more stuff that will fail all over. they should be doing 'sudo su -'.
I'm not sure how many ebuilds explicitly require the sbins in PATH; If it turns out to be quite a few, probably wouldn't be a bad idea to have portage set it by default. As is, I use sudo emerge quite a bit (as do others I'd suspect), and haven't seen to much borkage- doesn't mean it's not there, just that I haven't noticed it yet :)
in cvs.