What do you mean? Is that considered too deep nesting? (I'm not trying to be sarcastic.)
My problem with this code is not aesthetics. This logic is too deeply nested, by the time you hit the last conditional there is way too much going on[1].
Perl makes it especially nice to flatten logic due to RHS conditionals, eg "x++ if y;". Here is my two minute flattening job[2], it prob has syntactic errors but you get the gist.
[1] http://en.wikipedia.org/wiki/The_Magical_Number_Seven,_Plus_...
Seriously though, I use maps and greps a lot now, often chained to transform a data structure from one type to another. I'm annoyed when I have to drop to a for(each) loop.