iOS 4.1 and iTunes 10

Although it may be tempting to update to iOS 4.1 when it comes out, make sure you pay heed to the Dev Team warnings.


  1. iOS 4.1 is not currently jailbroken - you WILL lose your jailbreak
  2. iOS 4.1 contains a new baseband - you WILL lose your carrier unlock as provided by ultrasn0w.
  3. If you ignore the warning and update to 4.1, you can downgrade to whatever version you have SHSH for (either locally or on-file at Cydia. So if TinyUmbrella shows SHSH for 4.0.1, you can downgrade to that version. That said - you cannot downgrade your baseband /ever/. Once you update to a firmware with a new baseband, you are stuck on that baseband regardless of firmware downgrade.
I plan on supporting iOS 4.1 when it is released and hopefully I'll have the UI changes as well as the rare PPC / crash issues worked out.
I've taken a quick look at iTunes 10 and don't see any immediate issues with local restores but as always, please hold off on updating to new versions of iTunes unless you absolutely have to have a feature it provides.