KDE-Forum.org

The latest Kubuntu has KDE 4.1 in its repository.

check kubuntu.org for the info about the release of 4.1 for it. you have to add one repository to your sources list, but doing that and the install process are completely trivial. what hiccups did you have? perhaps we can help with those...

but for what you're saying, for it to be the standard build, you'd have to go with kubuntu 8.10, which is in alpha. it actually defaults to kde4, see notes:
"The third alpha release for Kubuntu Intrepid is available now for early testers. This release uses .kde instead of .kde4 for KDE settings so you will be unable to easily downgrade to KDE 3. See the announcement for more information or download it directly."

but that was on july 25. the 4th alpha will be out aug 14th. although the repos for those alphas get updated all the time. as for other distros, i don't think anyone has 4.1 in yet and has their distro out of alpha/beta. if they do, then it's probably a pretty thrown together distro! my recommendation is to go with kubuntu 8.04, and just add the repo. it's easy and although i've had some fun using betas in the past, i ended up finded them too frustrating until release candidates come (i don't program, and reporting bugs pre RCs seemed pointless, since things were often changing so fast. then the constant updates to the repositories annoyed me, because i'm unable to resist upgrading packages whenever updates are available...)

just my 2 cents,
jet

I use archlinux. the nice thing is it's BSD style init scripts and minimal default install so you can quickly build the system you want. 'pacman' is also a rather nice package manager as well imo

I am using arch linux too, and I love it!

pacman is god