Having recently bought (still waiting for it to arrive though) a lightweight laptop; (think netbook but with more spec); I was completely disgusted with the fact that none, not a single one, of the new laptops I could find were shipping with anything other than Windows on them. (Mac excluded for the moment). This is after the whole 'linux is making huge inroads into the netbook market' story - which, I suspect, they are, in (say) India. I even went to the US Dell site to have a look, after a hit to a story which blew Dell's trumpet with the 'giving customers a choice of OS' lie.
Dell US does offer, oh, 5? laptops/netbooks preinstalled with Linux; however to get to them you can't just go through the netbook -> customise my netbook -> select OS option (there you get to pick windows, and if you're lucky, windows); no; you need to go to the Dell Linux homepage and then shop. Even then, if memory serves me right, not one laptop was a direct comparison of spec - nowhere could you get to the point where you said 'Ah! I'm being charged $xx for Windows on this PC when Linux ships free' as the other specs were not the same.
I reckon M$ has threatened suppliers with withdrawing rights to sell unless they're given monopoly; just like they refused to let the dumbed-down versions of Windows be installed on netbooks unless thye were limited to 1Gb RAM, 160Gb HDD; which has effectively capped the entire netbook market at the same spec even though it should be perfectly possible to make them, for the size, much more powerful now.
/end rant