iOS 4 will be Released Tommorow, Update or Not?

Apple will push iOS 4 final version tomorrow on June 21st so I decided to write this article about the Final Version of iOS 4 for iPhone and iPod Touch, In this article I will be covering everything you need to know before updating to iOS 4 including Jailbreak, Device Support, Compatible Apps, iTunes, and More!

iTunes Update?
Apple has already pushed iTunes 9.2 for public for both Windows and Mac users, But the iPhone Dev Team advised us not to update iTunes to iTunes 9.2 version because you may can't jailbreak after the update but msf.guy already showed how to Jailbreak using PwangeTool Bundles, more Details posted here.

Jailbreak?
Don't Update if you got a Jailbroken iPhone using Spirit, comex the developer of untethered Spirit Jailbreak tool for iPhone, iPod Touch and iPad has tweeted advicing people not to Update to iTunes 9.2 (This means not to update iOS 4) if you already have a jailbroken iPhone or iPod touch.

DO NOT UPDATE TO ITUNES 9.2 IF YOU ARE USING SPIRIT until I learn what's going on.

But Don't forget that Dev Team will release Redsn0w 0.9.5 final version to Jailbreak iOS 4 tomorrow when it got released by Apple so I advice you not to update till they Release Redsn0w, You can stay tuned on Twitter or on Facebook.


Unlock?
Oh, forgot about the Unlock, MuscleNerd a trusted person in the iPhone Dev Team has confirmed that iOS 4 on both baseband 05.12 and 05.13 will be unlockable and probably on iPhone 4 Also! Just Keep around for the Guide about the Unlock whenever it's released.

Apps?
iOS 4 got a new amazing Feature which is Multitasking between Apps, So developers have to update their Apps for iOS 4 compatibility. If you are going to update to iOS 4 tomorrow then Make sure to update your Apps too.
Update: Just added a list of Apps ready for iOS 4 with Multitasking features, Check the List posted here.

Backup and Save SHSH
You decided to update, then don't forget to back up SHSH Blobs as Apple prevents you from downgrading unless you’ve got a backup of your personalized SHSH blobs. I already posted Full Step by Step guide to Save SHSH of iPhone 3.1.3 for Windows and Mac users, Guide posted here.
Backup: Download iTunes 9.2 and run a manual backup (right click on your phone in iTunes, hit backup)

Device Compatibility
iOS 4 will be fully compatible with iPhone 3GS and iPod touch 3G but iPhone 3G and iPod touch 2G won't get multitasking, custom wallpaper, and Bluetooth keyboard support as Apple maintains the hardware isn’t capable. But comex is working on making iOS 4 available on iPhone 3G and 2G Also! But bad new for iPad users, iOS 4 will not be compatible with iPad!!

Missed Something?
Hope that I didn't miss anything and I covered all you need to Know before updating to iOS 4, But if I missed something Hope you let me know by the comment section below :)