Some good news out of the ASUS camp this morning, as it appears the Transformer Pad TF300 is in the midst of getting its promised update to Android 4.1.1 Jelly Bean. Erckul and prissysox in our forums are leading the way on this one, noting that you're warned Adobe Flash is no longer working (but you knew that already), and that apparently Wifi Direct took a hit as well.
The update appears to only be over-the-air at the moment, so keep an eye out.
http://www.androidcentral.com/asus-transformer-pad-tf300-gets-its-jelly-bean-update