Planetbeing and MuscleNerd were working a lot the last few weeks to unlock our iPhone 4s on Baseband 01.59.00, they were waiting for comex's jailbreak to be released and it was released couple of days ago but there was some problems so the unlock was delayed! Now they just delivered the unlock and you can now free your iPhone 4 from AT&T Carrier with Ultrasn0w 1.0-1.
Note: For T-Mobile users, you have to Disable 3G Mode, Just touch on Settings --> General --> Network.
 
Step 1: You should have a jailbroken iPhone 4, you can follow the step by step guide to Jailbreak iPhone 4 posted here.

If you are waiting for the unlock and can't stop yourself from seeking around for any updates about the release, then don't worry, Planetbeing has confirmed that it will be out tonight for all people who are waiting for iPhone 4 carrier unlock using Ultrasn0w 1.0-1

For all who asking about the new update of Ultrasn0w to unlock iPhone 4, it's ready and will be released later this evening. In less than six hours, Ultrasn0w 1.0-1 will be released to unlock iPhone 4, iPhone 3GS and 3G. It's compatible with all basebands including the new baseband of iPhone 4 (BB 01.59.00)

We will inform you whenever the Unlock is ready, in meantime while waiting for the unlock you can jailbreak your iPhone 4 with JailbreakMe 2.0 by following the step by step guide posted here.

Today, Planetbeing has dropped a new app in Cydia for iPhone 4, This app maps the cell towers you are connected to and displays detailed cellular information from the baseband, Of course you need a jailbroken iPhone 4 to install this app.

Good News to get the hopes up, in an all-star podcast interview with Comex, Planetbeing, Chpwn, and Saurik yesterday, Comex was asked "When is the iPhone 4 Jailbreak and Unlock is going to be released?", the answer was great "pretty close to done"

Well, Planetbeing today has posted on his twitter account that he has already updated to iOS 4.0.1 on his iPhone 4and that was a good thing to find that it's unlockable with taller bars. This unlock is the one that Planetbeing used before and Musclenerd said that it's the best and they will use it on the new update for Ultrasn0w.

Today we have good news, MuscleNerd talked about unlocking iPhone 4, He said that you can Unlock iPhone 4 permanently without need to Ultrasn0w by getting the codes out of the seczone to calculate your NCK code, But this Process will have to go over 100 trillion combinations. So in a tweet answering someone who don't understand telling him that the Unlock is ready and he is waiting for public Jailbreak release from comex.

Couple of Days ago, iPhone 4 Unlocked by Planetbeing and MuscleNerd, But Today they got another Method to Unlock iPhone 4 and it worked, MuscleNerd is saying that they have 3 ideas / Methods to Unock iPhone 4, He will try them then find the best and rewrite Ultrasn0w then adds it to Cydia!

So Stay Tuned for Jailbreak and Unlock Release Soon! [via Twitter]

Planetbeing is demoing iPhone 4 Unlock after some hours of Saying that he got his iPhone 4 Unlocked and Jailbroken, He also showed us Cydia on iPhone 4, Now he shows a demo video for the iPhone 4 Unlock in brief, Enjoy by Watching the video below..

So, Let's begin the Count Down.. Stay Tuned

Yes, Planetbeing has just posted a screenshot his twitter account for his iPhone 4 unlocked (previously) and jailbroken now, The Screenshot below shows iPhone 4 Unlocked and Jailbroken, as Cydia appears down with a list of apps.
Here's the tweet form Planetbeing

Yes, You read it right! Planetbeing has just managed to Unlock iPhone 4, Planetbeing has finally unlocked his iPhone 4. He has posted on his twitter account that he got his iPhone 4 Unlocked! So Let's  beigin the Countdown for Release Time.

iPhone Dev Team has been working for a week on the Unlock, they already made Good progress by Planetbeing and MuscleNerd. Couple of days ago, MuscleNerd said that they are one step closer (details here), But Today, He confirmed that they reached to this step and they Got Full iPhone 4 bars.

Yeah, they are about to Unlock iPhone 4, MuscleNerd has just tweeted that he and Planetbeing are in Progress in iPhne 4 Unlock and may hit the web at any moment, they already got the bootrom of the iPhone 4 and compared it to the one of the iPhone 3GS.

Good progress on iPhone4 unlock with @planetbeing: http://is.gd/dh2WE <-injected cmd! (Akin to http://is.gd/dh2Ze on 3G)

Yes, Good news for all who got iPhone 4 and want to Unlock it, MuscleNerd and Planetbeing started working on that, They are working right now together on iPhone 4 new Baseband Unlock. Guys remember they are the iPhone Dev Team which we all Trust (especially me)

Planetbeing, one of the iPhone Dev Team has just posted on his twitter account that it's possible to develop exploits that could work on the future and not only on the iOS 4. This Jailbreak tool may be Comex's tool "Spirit" which was updated to fix iTunes 9.2 from couple of days.