Stable release of cyanogenmod 10.1 was released recently. It is based on Android 4.2 (jellybean) and is available for download for Asus transformer pad infinity / TF700T.
You may also want to download latest Google apps which aren’t included in cyanogenmod.
One has to download the unlock device app from Asus support site. Search for TF700T, select operating system Android and go to tools. Warranty is lost after installing the app!
TWRP ist a recovery manager with touch user interface and is available for TF700T.
The easiest way to install twrp is via ROM manager app goo manager. Unfortunately this app needs root permissions. You can get these permissions by using motochopper for your TF700T with Android 4.0-4.2.
With booting TWRP one should make a backup of currently installed ROM and data, wipe caches and install cyanogenmod 10.1.