This was supposed to be resolved in Titanium SDK 3.2.0.GA with the pull request dated 12/5 (https://github.com/appcelerator/titanium_mobile/commit/8e1f1c4a3734d5696383afca1c30765bac4f33b5) showing the changes.
However, the sdcard property isnt on the emu object at the time you try to debug.
Quick and dirty fix is to hack the sdk.
Line 1302 of {sdk}/android/cli/commands/_build.js has
} else if (!emu.sdcard) {
Replace that with:
} else if (!emu.sdcard && (emu.type !== 'genymotion')) {
and it should have you debugging.