Plenty of people seem to like the idea of Hybrid SLI and CrossFire, but Microsoft clearly isn't so keen; stating in its Guidelines for Graphics in Windows 7 document that it won't be natively supporting it in the new operating system.
This, in itself, isn't that surprising: why should Microsoft do nVidia's and ATI's work for them? However, the document goes one step further, stating that hybrid graphics "can be unstable and provide a poor user experience" and that it would discourage manufacturers from utilising the technology in its systems. It's the latter that will probably perturb the likes of nVidia, since it has invested a fair amount in this technology, especially surrounding its new integrated graphics chipset, 9400M - that found in the new MacBooks.
Ultimately, however, it seems unlikely that Microsoft can sway manufacturers to such a great extent. There appears, at least, to be some demand for Hybrid SLI and Crossfire, particularly in smaller and lighter notebooks, so whether the big boy in the playground approves or not is moot.
Do you want Hybird SLI and Crossfire in your notebooks? Let us know in the comments.