I'm not the BL expert, but the most important ones are:

- 4.6 has the RSA exploit, that is used by IPSF and GeoIPSF, fixed
- 4.6 allows only baseband upgrades. You cannot reflash the current one, nor previous ones. It does this by requiring a secpack with a version greater than the version of the current firmware.

These are the things that blocked the 3.9 exploits used in unlocking. There are others, I'm sure.

^^^
but you can now downgrade the 4.03 bb on 4.6 to 4.02 so thats not quite true now

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SEARCH!!! Its really not that hard!!

Can someone explain why we hate or love either of these guys? I guess we are where we are because they do both find ways to do what we all wan't. As far as I'm concerned they are both damn good at what they are doing. And I guess they trigger each other to move forward! I guess it's competition my friends! Whatch, enjoy and help them!

So how do we all benefit from this?

Update: He just lost a phone (probably permanent brick) in the process. Hope he continues with the project

That's bad, but that is the risk of working with such a low level part of the phone. Still the phone is recoverable, at least with an external flash (TA_Mobile style)

Seriously, lets really hope he keeps on doing it. We still need to get 4.03.13_G running unlocked on 4.6BL phones (at this time only 3.9BL phones can do it).

well im quiet sure with this everyone on 3.9 or 4.6 will want to have moded version. Since it will most likely be "open" for anything, upgrading downgrading BB without valid secpack, erasing/writing to zones that are locked otherwise, removed token/lock checks etc custom BL will be probably true unlock for all current BL and all BB in the future. All that custom BL should also be able to do is remove activation and JB for you, hah

... I really hate myself for saying this, but... *seems* the only ones standing still are dev-elite team: not even an update, in weeks, at their status page.
(1.1.3 soft-update? c'mon... that's just to keep people busy! )

Please, please, please: could you give to the community at least the "impression" something is moving? Or, if you are holding unbelievable achievements... could you, please, state it?

PLEASE!

yeah, but you know that playing with the bootloader is very dangerous right? one bad move and you end with an almost for sure brick (as geohot just posted in his blog)

Interesting nevertheless

I see this hack as a step towards custom cooked firmwares/roms like the ones available for windows mobile phones

One could end with a custom bootloader which points to a patching instructions file, so everytime a new firmware is released, this file gets updated and voila!

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3GS>blackra1n RC3>Restored to 3.1.2>Spirit>Unlocked 3.1.2 Untethered
3G>redsn0w 0.72>ultrasn0w>Unlocked 3.0>pwnage 3.14>Unlocked 3.1.2
2G>hardware unlock>elite-team virginizer>upgrade to 1.1.1>toc2rta jailbreak>anysim 1.1>unlocked 1.1.1>Restored to 1.1.3>Ziphone 2.2>Unlocked 1.1.3>Modified Ziphone>iClarified unlock patch>Unlocked 1.1.4>QuickPWN>2.0.2>2.1>2.2>2.2.1>redsn0w 0.71>Unlocked 3.0

I don't know how the bootloader and the baseband interact in the activation and jailbreaking process.

Activation and jailbreaking are done at the OS level. Activation is handled by the lockdownd daemon, and jailbreaking is just a minor modification to the fstab file to allow write access to the system partition (that has execution privilege) and optionally execute permition to the user/data partition (that has write privilege). I fail to see how any magical BL and baseband will be able to make any change to that.