here's a nice paper on debian called "why debian":
http://people.debian.org/~srivasta/t...bian/talk.html
i haven't found an equivalent paper for slackware, though... if anyone has a link to a slackware advocacy paper please do share...
i'd say that, in a nutshell (and IMHO), debian's greatest
pro is it's rock-solid stability... the fact that after they make a stable release only critical patches are provided (no new features) is a great thing, specially for mission-critical environments where stability is paramount... also, the huge package developer/maintainer community that debian has is one of it's strongest features IMHO... plus the amount of testing that goes into the packages, etc... there's a lot to like in debian (and in slackware also, of course)...
slackware... IMHO it's greatest
pro is it's uber-simple design... slackware sticks to the KISS principle and that's something that most slackers really appreciate... it uses a BSD-ish init system and the package format is basically gzipped binary tarballs... no (official) fancy automagical package manager... all in all, it's kinda hard to explain exactly why slackware is so delicious... maybe it's the way in which the slackware maintainer does his thing and has been doing it for over 10 years... maybe it's the educational experience of doing all the system administration tasks from the CLI... maybe it's the modern (compared to debian stable/testing) vanilla-flavored assortment of packages it comes with... also maybe the big user community here at LQ in the slackware forum... it could be many things...
one thing i know for sure is that debian and slackware do a lot of things differently and honestly i think that's a good thing for both of them... i mean, there's situations when debian is probably the best option, and there's situations when slackware is probably the one...
which one are you currently most interested in?? why??