ASUS is following through on a promised they made last month to bring Jelly Bean to their tablets. According to a post on their Facebook wall the first tablet to be graced with OS 4.1.1 is the Transformer Pad TF300. This was released in Canada last in May and ASUS also states they’ve added a new power saving options, global file search and unknown “improvements to the pre-installed apps.” The upgrade should be waiting for those who have the 10-inch tablet OTA, check Settings > System Firmware Update > Check Update.
As for the other Transformer Pad Series tablets, ASIS will be upgrading those to Jelly Bean sometime “in the near future.”
Source: ASUS Facebook