Please find the attached binaries for the Windows RT version of ioQuake3 - http://ioquake3.org/
The pak files are not included, so you will need to follow the instructions on the ioQuake3 pages/wiki to install those.
Many thanks to windowsrtc for finding the D3D9 runtime and building the opengl wrapper. All of the necessary runtime binaries are also included in the package. You can also use these runtime files for my ports of Quake and Quake2 to enable much speedier opengl support. Performance in Quake3 is decent at approximately 30 fps on my Surface RT.
EDIT: so, i ran across this video on youtube -- http://www.youtube.com/watch?v=XXZc0eDydtA -- which pointed out that connecting to internet servers might not be working quite right. I think it should all be fixed now, as I was able to connect to servers on the internet and frag some bots. Please download the 'rel2' binaries if you'd like a fix for this issue. Cheers!
EDIT2: bit of fail on my part, I had improperly named the D3D9 runtime file in the 'rel2' release. Fixed now. Sorry all.