I have installed iOS 5 on my devices at first I had some problems with a error 3200 in iTunes. But that was from that Apples servers was overloading with everybody upgrading.
Some suggestions before upgrading if you haven’t done this.
1. Remove any apps that you rarely use
2. Make sure that you have updated all apps in your device
3. Make a backup copy of all your photos and remove them from the device
4. Remove and videos and music that you can
All the above things is just so you upgrade goes as smooth as possible, If you have alot of data on your device the backup will be huge and take alot of time.
Also before you start upgrade, make sure that you have Itunes 10.5
Start the upgrade and don’t be scared it will do alot of reboots before it’s done.
Happy upgrading 😉
One thing that similar between Apple and the Domino server is that upgrades is always that smooth.
If only the Notes Client install could be that smooth too.