Don't get too hung up on the actual mobo. Pick a mobo that is known to work well with Kubuntu 0710.
I'd just like to point out that I personally have used a mobo which worked great in kubuntu, but caused random crashes in LMCE. It's not a perfect correlation. But, 8.10 should provide alot more hardware support purely from the newer kernel.
That's always possible - if LMCE uses some feature that doesn't commonly get used in Kubuntu. An example is the Intel GMA950 GPU with the Photo Screen Saver. But that is fairly rare, in fact that's the only specific example I can think of... which I dealt with by recommending nVidia GPUs in that post. If you used some other program in Kubuntu on that mobo, that used the same OpenGL feature, then it would have done exactly the same thing and crashed.... so I think working great in Kubuntu is a bit subjective... it depends on what you do, alot.