Today Apple has released 3.1.2 (7D11) firmware update.
According to the release notes, it fixes for the following issues:

• Resolves sporadic issue that may cause iPhone to not
wake from sleep
• Resolves intermittent issue that may interrupt cellular
network services until restart
• Fixes bug that could cause occasional crash during
video streaming

There is no new baseband update in this firmware release.

The update can be downloaded from Apple via this direct link: iPhone1,1_3.1.2_7D11_Restore.ipsw

As always, the iPhone Dev-Team warns against the update if you care about jailbreak and/or hacktivation, as there are currently no jailbreaking tools compatible with 3.1.2.

However, it is possible to update (not restore) from 3.1 while keeping activation.

__________________
Waiting for iPhone3,1...

Could anyone confirm this? Since Apple changed the way hacktivation is handled in the 3.0 and 3.1 releases, I'm a little afraid of hitting the update button right now. Don't want to go through the whole restoring and re-syncing procedure without profiting from it, thats what I will have to do when the update fails.

Hi,

Upgrading from 3.1 (pawned, unlocked) towards 3.1.2 does not work. You will be locked again.

It is possible to keep activation after updating to 3.1.2 if you follow these instructions.

Specifically, the key appears to be the upgrade from pwned 2.2.1 to 3.1. Then the update to 3.1.2 is just a single click in iTunes. Of course, if you decide to follow my steps, you may skip 3.1 and just go directly to 3.1.2.

I just wanted to confirm that my method allows to keep activation with subsequent updates.

__________________
Waiting for iPhone3,1...

Hi, I have an iPhone First Generation with os 3.01 and redsnow (unlock, jailbreak and hacktivation.) now i would like to update to 3.12. But what wil Happen with unlock, jailbreak and hacktivation? Thank you.