The Athlons only have motherboard based incompatibilties compared to the BX. The BX has been around so long it's rock solid stable and very mature (and kudos to intel for making such a powerful chipset that is still good almost 3 years after it was released).
But if you compare a KT133 board to a Pro 133A or even an i815, they all have some issues, and they all need updated INF files for Windows.
How about the i820 problems? Lets just not go there.
Unfortuatnely it seems the golden age of the BX is pretty well at it's end, and I don't see any chipsets that can match it for speed/stability/flexibility. Any newer chipsets from Intel, Via or AMD have some problems problems.
Up until you could compare a P3 on BX to AMD on whatever, and yes the intel side had less issues. But Intel's "official" P3 platform is the i820...I'm hoping they do a better job on the i850 for the P4, but if they don't they won't have BX to fall back on this time.
But like you said, we just have to wait a few months and see what AMD and Intel cook up.