Based on Debian, SimplyMEPIS is gaining lots of popularity - it's now on the top 4 in distrowatch for this month, exceeding Gentoo, Ubuntu and even Debian itself !

I'm not going to write a full reveiw about MEPIS. I'll just tell you why I like it and what I'd like to see fixed.

SimplyMEPIS is a LiveCD, you can run it directly from the CD-ROM or install it to your hard drive. Here is where things get nice - the easiest and fastest installation I've ever seen, with almost no questions asked. Now that's what I call newbie-friendly !

The Desktop itself is clean, everything runs out-of-the-box including mozilla with all the popular plugins (even windows WMV). Some apps just didn't fit the CD, but hey you've got apt-get! Almost all packages can be found in debian software pools, MEPIS is already configured to use a nice mix of "stable", "testing" and "unstable" pools. It also uses the MEPIS pool which includes packages that were modified by the MEPIS team.
That's the main reason I like MEPIS: it's basically a Debian system that simply WORKS without the hassle & long installation.

MEPIS tools include the installation program, System Center & User utilities. They're very easy to use but they're nowhere near Mandrake's Configuration Center. It was easy to setup the nvidia driver with TwinView from the system center - something I really liked.

I really hope people will give it a try, I'm sure many of you will keep it. I'm using it for a month now and I'm really satisfied with it.

Links:

MEPIS homepage: http://www.mepis.org
Many reviews: http://distrowatch.com/table.php?distribution=mepis

Advantages:

15-minutes installation
Debian-based (apt-get)
Everything works out-of-the-box
Hardware AutoDetection
Mozilla plugins!!
Nvidia Driver & settings

Disadvantages:

Needs more configuration tools

In a nutshell: You get a robust Debian system at a glance.