Just upgraded to IOS 4 for my 3GS. Went well except I lost all of my Cydia apps in the process. So I am now in the process of getting those functions back. Phone is still jailbroken, thankyou pwnage team! Just need to get them back. So I am creating the list of apps I lost and am reinstalling so I have a quicker reference for myself for next. As there is always a next time!

• Categories (folders and organization app) Using the built in folder system in IOS 4.0 and seems to be working well.
• Winterboard (theme customization app)
• five button dock (tweak to allow 5 buttons in the dock)
•  MyWi (no Rock) allows Internet sharing and tethering **as of today MyWi blows up the phone. Need a new release of the app for IOS 4.0
• Just installed MyWi 4.0 from Rock and all is well!