I upgraded two phones last night, one worked perfectly, the other was bricked! The device would switch on, show an apple logo, then a spinner, then after 5 minutes go back to the Apple logo and repeat in a horrible loop - presumably until the battery gave in!
The reason for this is the firmware upgrade failed to authorise with Apple servers correctly due to demand and trashed the device. Even the two button reset did nothing! But, no fear, there is no need to pop down to your nearest Apple Store or ring them up and wait in a long overwhelmed customer service queue. Just follow these instructions...
1. Hold down your home button and the on off button at the same time until the device switches off. (a hard reset)
2. Plug the device into iTunes and then hold down the home button (dont let go). The device will switch on, keep holding the home button. After a few seconds the device will reset and you will be shown the plug into iTunes graphic, which will then disappear, as you are plugged into iTunes. (I had to try this twice, but it did work)
3. Click on Restore and have another go at doing the upgrade.
If the Apple servers are still suffering from demand you may have to try it all again! However this morning (UK) everything seems to be working fine. I have just watched a iPad upgrade.
Hope this helps.
I have just about caught up after my trip to Silicon Valley, so normal regular blogging will kick off again!