And the winner is...

I might as well just stop blogging right now, because it might be over. I've found the perfect distro for me, and it was right under my nose the whole time. I'm writing this from Mandriva 2008, and so far, I don't see any reason to look beyond it (at least, for me to look beyond it) for a main distro.
Really, nothing much has changed since the 2007.1 release. The MCC is still one of the best Linux control centers around (for almost anything), balancing a keep-it-easy-for-the-user philosophy with flexibility and a policy of not requiring the whole base system to be contorted in all sorts of ways (unlike openSUSE's YaST). The winning combination of i586 optimization and parallel booting ensures lightning-fast performance, a trait Mandriva passes on to its evil son, PCLinuxOS, and without the bloat of some other optimized distros (coughcoughcoughSabayoncoughcoughcough), it makes a solid gaming distro.
But there were still some minor improvements this release. As is now tradition, Mandriva moved a step away from their corporate past by abolishing the "Mandriva Club", their VIP service for paying users. Version 2008 also comes with fresh applications and artwork, including, as always, a bleeding-edge GIMP version (2.4-rc2 this time). Compiz Fusion is now included by default, continuing the tradition of excellent 3D effects. Under the hood, Mandriva is now running Linux kernel 2.6.22.6 with CFQ I/O scheduling (not to be confused with CFS). There's a full list of changes for anyone interested.

Installation and... bells?

The installation and post-install configuration took about half an hour. I installed Mandriva right off my hard disk, but did a full KDE install from the enormous Free image, which didn't include iwlwifi drivers. I downloaded and installed them, and thanks to MCC, I had the system up and running in minutes.

I ran into a pleasant quirk: My system bell/beep never sounded. Turning it off had me tearing my hair out on openSUSE, and it was mildly annoying on Mint, but Mandriva shipped with it turned off. It's the little things that make Mandriva such a red-carpet distro.

Performance aka pwnage

GLXGears reported about 1150FPS, which was surprisingly low, but still better than most distros I've tested. I couldn't try out Tremulous because my ISP was apparently having a bad day, and it only works for online play.

OMGWTFBBQMETISSE?! aka 3D Effects

As usual, Mandriva ships with cutting-edge 3D effects. Last release introduced Beryl and Metisse. This time out, Mandriva ships with Compiz Fusion replacing both Beryl and Compiz. The drak3D wizard remain easy to use, with only 3 options: No acceleration, Compiz Fusion, or Metisse.

Other areas/Overview

Mandriva included both a traditional KDE menu and a shiny, usable (tabs switch when moused over- w00t) Kickoff menu, a la openSUSE and with a custom configuration and artwork.
Speaking of artwork, Mandriva shipped with a noticeable amount of polish on everything. The KDE panel has the now-ubiquitous "glossy" feel to it, and the new wallpaper, usplash, and login splash artwork gave it a distinct feel of continuity. The Kickoff menu had the same artwork as the default KDE menu, giving it a much more professional feel. Finally, although Mandriva is mainly a French-developed distro, the English translations were flawless, unlike *some* foreign distros I could mention...
Installing the task-kde4 package in RPMDrake gives you a complete KDE 4 desktop.
I don't know why I overlooked Mandriva as a distribution before. It's cutting-edge, friendly, fast, and respectful to hardcore Linux geeks. In other words, it's just like PCLinuxOS. :P Really, the only difference between Mandriva and PCLinuxOS is that Mandriva is more bleeding-edge and PCLOS is a tad faster. If you want a simple, often-updated, and cutting-edge desktop, Mandriva is worth a look as much as it was back in 1998.
Pros:
-Friendly without disrupting the traditional Linux setup
-Relatively fast
-Cutting-edge 3D effects
-MCC is as useful as it gets
Cons:
-Ubuntu is still better-supported
Friendliness: 5/5- As I remarked earlier, red-carpet service.
Performance: 4/5- By cutting down on bloat and optimizing for an i586 architecture, Mandriva is as much a gaming system as a workstation.
Features: 5/5- Bleeding-edge features, and a complete desktop out of the box.
Packaging: 4/5- RPMDrake is second only to Synaptic, which PCLinuxOS uses.
Artwork: 2/2.5- The artwork uses interchangeable color schemes, and is polished as usual.
Community: 2/2.5- Combine the Mandriva and PCLOS communities together and you get a hell of a lot of (relatively) happy tech-support for free.
Overall: 4.4/5- Mandriva's rise from their corporate ashes has been overshadowed by Ubuntu, but they're still very much alive.