Mandriva may remain on those Classmate PCs for Nigerian schoolchildren after all. See http://www.pcworld.com/article/id,139480/article.html?tk=nl_dnxnws
It seems Windows may still be on the table, but at least it's not a sure thing that Mandriva will be dumped. "Last week, Mandriva heard that TSC planned to pay Mandriva for its customization work -- but then abruptly change the OS on the computers to Windows XP. TSC had placed an order with a local Microsoft supplier for Windows XP and Office productivity software. The switch raised the question of why TSC would commit public money to buy computers with Mandriva, and then absorb the cost of buying Windows and installing it on the computers."