iOS4.1: Keyboard & Sim Issues?

Since upgrading, I have been experiencing problems with the keyboard, in which it appears to be totally uncalibrated at times. I can hit one part of the keyboard and it will highlight (as if pressed) a key which is elsewhere on the keyboard. Returningto the home screen and back to the text message fixes it.

I have also been getting a "No Sim" error roughly 3 times a day. Switching airplane mode on for about 5 seconds, then back off again usually fixes it but sometimes takes 2 attempts.

I used to work for Apple so am aware of the usual troubleshooting steps and what Apple offer in terms of their Genius bar, but I am trying to gauge whether this is iOS4.1 related and being seen by other people or whether it is simply an issue with my individual handset. I suspect its just my handset playing up.

I've restored the phone, but did restore settings from a backup. Sadly this has had no affect on the problems. Tonight I shall setup as a new phone after restoring to rule out a corrupt/dodgy backup