A healthy chuck of Linux Users is probably part of the 0,71 % Other OS. If you look at the "What's your current Distro and Desktop Enviroment"- Thread which has way almost 2000 posts there are craploads of Mint, Fedora and Arch Users in there. Mint also is recognized as seperate OS in the "System Information" and not declared as Ubuntu. It's unlikely that non of the other distros beat 12.10 32-Bit in terms of market share.