Late last night Amazon released version 6.2 of the Android-based operating system for their new and popular Kindle Fire tablet. Surprisingly, they neglected to include a change log identifying new features of the software. Reports indicate that the update provides better touchscreen responsiveness and a few other updates that improve the overall user experience.

A couple features of the update, however, have people talking. First, the update was installed automatically for most users. That is, they were not given the option of delaying or declining the download. Second, the update wipes out the modifications made by users who have rooted their devices. Rooting, roughly equivalent to jailbreaking in the iPhone world, allows users to make changes to the operating system beyond those allowed by the manufacturer. In the case of the Kindle Fire tablets, it allows access to the Android App Market, in addition to Amazon’s own App Store. Version 6.2 of the Kindle Fire operating system removes any modifications made to rooted devices, as well as removing access to the App Market. In some cases it even appears to be removing apps downloaded from the App Market.

Some Twitter reactions to the update focus on the improvements in functionality.

Other users reacted against the update’s impact on rooted devices, and the stealthy way in which Amazon delivered it.

Users who have rooted their Kindle Fires need not be too worried, however. Unlike Apple, which routinely changes iOS to make jailbreaking more difficult, Amazon appears not to have made any effort to prevent users from re-rooting their devices, making the change little more than an inconvenience to those users. The question remains, however, as to whether future updates will take a more aggressive stance toward rooted devices.

The Kindle Fire, which released just two weeks ago, is thought to be responsible for the record Black Friday sales Amazon reported for the Kindle family of devices this year.

What do you think about Amazon’s secret update? Should they have left rooted devices alone? Let us know in the comments.