No. $nick($chan,0) gives you all nicks on the channel regardless of status. Regulars are the ones who aren't opped/voiced/etc (as mentioned).
$nick($chan,0,r) gives you the number of regular users.
$nick($chan,0,v) gives you the number of voiced users.
$nick($chan,0,o) gives you the number of opped users.
Note that you can use # instead of $chan, but I never like using that. I think $chan is more appropriate, but that's just my opinion.
