I think they are just saying that DX10 doesn't work in SLI right now. So DX10 itself works just reverts to one card if you are running SLI, not perfect but still functional.
Well that is the whole point of the post above, and the article itself specifically stating that very thing that DX10 SLi support is still Beta.
I noticed he didn't want to finish Theo's sentence, so here's the actual quote to which Red was replying;
"We don't have confirmation of DX10 drivers for 64-bit operating systems, but we have been assured that the driver support will be second to none and that AMD now has a levy over Nvidia measured in weeks - WHQL SLI driver for DirectX 10 or 64-bit Vista isn't expected until April - which is pretty sad."
Seems pretty focused on DX10 and SLi. although the 64bit version does support regular SLi like the 32 bit version, but BOTH don't support DX10 SLi, which may have been the point.
It'd be interesting to see if anything had to be made 'optional' in order to pass qualification. A few thing in the trouble list still interesting like multi-monitor support and LCD scaling (guess S4fun missed that one).
Main thing this means now is that DELL can start shipping SLi Vista rigs for their XPS customers, but with the cavea in small type somewhere than DX10 SLi isn't supported (not that it's really gonna matter for a while to come).