Rooting Was Easier This Time
This is not the first time a device has been rooted prior to its release (by means of a leaked release candidate of the SGS3 firmware), but apparently it was actually easier to achieve root on Samsung’s latest flagship than it was on previous Samsung Galaxy S generations. Chainfire said on his XDA thread that Samsung is using the standard boot.img format for its stock kernel (as it does in the Galaxy Nexus) rather than the zImage format that prior Galaxy S versions featured.
This format is easier to repackage as a rooted boot image, which, as Chainfire’s post on XDA said, “any serious dev on this board can do the same thing in 10 minutes.” Don’t expect the “insecure” kernel posted in that thread to be the final rooting solution after the device is released, though. Likely rooting, in its final form, will involve flashing a custom recovery like ClockworkMod through Odin and achieving root through that recovery, since it’s firmware independent.
Leaked Firmware Now Available
The XDA thread now contains the leaked, rooted firmware, so those of you who get the SGS3 will already have root access waiting for you. Also, those of you who want to copy apk's and test them on other ROMs are sure to have a field day, though much of the reaction to S-Voice expressed by devs and rooted users alike has been less than encouraging. Apparently, the issue is not as much with bugs or porting issues as it is with the flaws and inaccuracies of the voice-recognition technology itself.
I imagine that other features such as the ripple lockscreen and the improved camera software will soon find its way to other devices, especially the Galaxy Nexus. However, other features such as the picture-in-picture video player that allows for watching videos in a small popup window while you perform other tasks, will likely be far more difficult to port.
It should be noted that the firmware and kernel posted by Chainfire are only for the international version of the SGS3. U.S. versions of the SGS3, featuring different CPU/GPU chipsets, will likely also feature different kernels and different firmware.
Will This Root Remain?
Since the firmware leak was of a release candidate, Samsung still has the option of changing its bootloaders and kernel to block this root method, though this is rather unlikely. The trend, being pushed primarily by U.S. carriers, has been for Android phone manufacturers to lock down their phones in order to prevent custom kernels from being installed, so it remains to be seen if Samsung will fall in line with other major OEMs Motorola and HTC in locking down its bootloaders.
HTC and Motorola have made token efforts to reach out to the developer community (HTC making more serious efforts than Motorola) by providing unlock methods for their phones. For example, Motorola provided an unlock method for its international RAZR phones, but its Verizon devices remain locked. Meanwhile, HTC has provided unlock solutions for most of its phones, even in the U.S., but the AT&T version of the One X remains locked.
Out of the three major Android phone manufacturers in the U.S. market, Samsung has been the lone holdout from locking its bootloaders. Hopefully this will not change with the domestic release of the Galaxy S3, but pressure on manufacturers from the carriers (especially AT&T and Verizon) to lock their phones down remains intense. Still, it is highly unlikely that Samsung would make such a drastic change so late in the game.
Update: S-Voice Gets Silenced
Just this morning, PhoneArena reported that Samsung has blocked its Vlingo-powered S-Voice service to devices other than the SGS3, which means that if you downloaded the app pulled from the firmware leak, you'll find a deafening silence to greet you. Until some elite hacker finds a way to spoof the app into thinking your phone actually is a SGS3, you'll have to settle for an alternative voice assistant app.