Basically we are going to revert to .15 Root, install Rootkeeper and then update:
Original Directions: http://forum.xda-developers.com/showthread.php?t=1622628
Execute Method #2. Only you are responsible for damage to your device.
ORIGINAL OUTDATED POST BELOW:
Still no word on root yet for locked bootloader devices. Personally I think google just did an about face with its open source policy by requiring ASUS to lock and encrypt the bootloader. I had this device when the bootloader was still unlocked. I do not want to unlock my bootloader as it voids the warranty.
The only way to achieve root on .21 at this time is to use Rootkeeper before upgrading or to unlock and root with a rooted rom. On my HTC phone this wasn't an issue, but my prime creaks when I tap it certain ways and it makes me want to hold on to that warranty. Once I do unlock I will want to try out UNBUNTU and a ROM that supports dual windows. (Why? --- Privacy Concerns, Real OS). Check out what's cooking for the TF201 at XDA.
I think there is a small possibility that ASUS allows unlock without losing warranty soon. Why--
- Other Manufactures do it, including those with comparable tegra 3 devices
- Essentially they are selling the equivalent of windows without administrator privileges at some point the government may step in and regulate
- There are obviously a significant number of users with pure hardware issues, this can be surmised from the low delivery/yield numbers and high return rates.
- ASUS has already faced one lawsuit over the tf201 functioning, they need to buy some "goodwill" if they don't want to get hit with more because they are in an actionable position
- best case scenario for ASUS they spend millions on a winning defense with no recourse for attorneys fees
- worst case could be a forced recall
Hopefully ASUS can embrace the developer community and start integrating some of their updated code which may actually help them fix the random reboots and terrible browsing which they have been unable to adequately address thus far.
Upcoming. Read about possible causes of Transformer Prime and tf300 slowdown