Debian For Me.
Advantages: Debian Lenny will be perhaps the stablest Distribution currently.Debian Community is paranoid on security fixes ASAP.
Debian Testing with unstable and Experimental(apt-pinned) together can give you a Fresh Linux experience with No Customized("bugged") packages as done by Ubuntu.
Debian Experimental got almost 90% of Gnome-2.24 available with fresh updates to latest versions.
few Ubuntu packages like Upstart event based init daemon are available in Debian via Project Utnubu.
I am a fan of Debian Social Contract.their packages(official) are guide lined by DFSG.
FrontPage - Debian Wiki
Disadvantages: Stability comes at a price for Debian Lenny.The package versions are freezed long back.for eg: you will find Gnome @ version-2.22!!!
.(For Kde ,there is unofficial backports for latest Kde).although ,I agree a server or any mission-critical applications won't have even gui's and other harnesses.
If using apt-pinning with testing(as base) and unstable, experimental repositories ,it will need you to be a little experience with broken packages(dpkg --force-overwrite) and comfortable with reporting bugs of packages you find(if possible fixes too).
Daily updates will come anything from 15MB to 100MB!
.but that is fun,and you won't lose anything if scheduled for download and install during Happy Hours(for eg: dataone).
and remember Ubuntu comes from a snapshot of Debian Unstable(Sid) branch.:cool2:
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Debian needs some experience with GNU/Linux before jumping inn.I had a Debian system for around 2.5 years.
