Microsoft has issue a Firmware update for the Surface. The Firmware update includes a wifi fix which hopefully will fix the intermittent problem I have where it doesn’t join a network correctly. There are also updates for Windows RT (kb2808380) and updates for Office 2013 RT.
The updates came in at just under 100mb on my Surface RT and require a reboot after downloading. The updates should come down automatically via Windows Update or you check for yourself by going to Settings/Windows Update.