According to the article, the bug "can degrade performance when video or other graphical data is processed through a PCI bus. . . ." Data corruption is also a possibility. A fix is planned in the "relatively near future", whatever that means.
Obviously this isn't going to affect too many people, since PCI video cards have been almost completely relegated to pulling second monitor duty (unless you have a Mac, of course). Add in the affordability of AGP cards with dual monitor support and the bug becomes a tiny footnote.
Of course, the notable exception to this rule is those "gotta have it" power users who want both dual monitor support and better 3D performance than a GeForce MX can offer. You know, the sorts of users who would buy a P4 system as soon as it came out.