If you've used Mandriva Linux, you'll feel right at home with Mageia. Mandriva has always had a reputation of working well for both the novice user and the power user. Installation is typically easy and hardware support is among the best of any distro. The user and administrative tools are comprehensive and easy to use. Of course, under the hood, it's all Linux and all configuration files are plain text files and all a competent administrator needs do is to choose a shell and a text editor.
Mandriva has also been known for excellent default fully-featured configurations of the KDE, GNOME, XFCE and LXDE desktop environments as well as a broad range of available applications. Mageia is no exception in this regard.
For the average user, the changes are mostly cosmetic. The Mageia art, colors and graphics are very well done (and contributed by the Mageia user community). But if it's just a pretty Mandriva, why is there a need for another Linux distro?
Mandriva began life as Mandrake Linux, based on Red Hat 5; Mandrake was essentially "Red Hat Done Better". It offered a well-configured KDE as the default desktop as well as its own administrative tools that provided more flexibility than those tools offered by Red Hat. The under-the-hood difference in these tools was that they were (and continue to be) written in perl language rather than the python language as used by Red Hat. Mandrake/Mandriva also spent considerable effort on its unique urpmi package management tool, essentially an intelligent, powerful console/gui wrapper around the RPM system of package management.
At some point, the business management of Mandrake/Mandriva lost its way, rallied, re-grouped and then lost its way again. The first time, they lost focus on Linux and the second time, they lost focus on their community. Mageia stepped in to fill the void in the community so that all the good things that were represented by the Mandriva distro would not be lost in the corporate buyout.
Which is why the software is so similar and the community is so different; you only need to fix what is broken.
Mageia offers the most recent version of your favorite application software and all the major software you expect to be there is there. Mageia uses kernel 126.96.36.199 with additional patches for automatic process grouping and Transparent Huge Page support as well as support for AMD Fusion APUs and Intel Sandy Bridge and Panther Point chipsets.
Both 32-bit and 64-bit installation DVDs as well as a Live CD are available. Migration from existing Mandriva 2010.2 installations is easily done. A large on-line software repository is available and provides a wide range of software of both free licensed and other licensed categories (the latter is not enabled by default, but is opt-in).
As with any initial release, you're likely to find a few minor bugs, but the Mageia community is there to help you. As a long-time user of Mandrake/Mandriva and co-author with Bill Ball of the Red Hat/Fedora Unleashed series, I believe you'll find Mageia a full-featured and easy-to-use Linux distro.
UPDATE: Mageia5 is released on June 2015; upgrades are very easy and have given me no problems.