You do realise of course that Webalizer was originally written in Perl? It was only later, once the feature set had settled down that the author rewrote in C for speed? For heavy traffic sites where you're crunching millions of lines per day, the decrease in run time is appreciable.

In the eight years or so I've been using Webalizer, none of the other applications I've evaluated have shown themselves to be better. awstats may be flashier (Webalizer is pretty stodgy), but I don't find its results as useful.

I do like Visitors a lot. It's fast and its results are gorgeous. It just doesn't do history as well as Webalizer, but in other respects it's quite complementary.