This has me a little interested, the fact this new dongle will work with iPhone 4.
http://store.apple.com/us/product/MC953ZM/A?mco=MTY3ODQ5OTY
The way it reads though is that unlike with the iPad 2, other iDevices can only output certain videos/apps to the external display, not complete mirroring like the iPad 2 does.
I assume this is a limitation of the hardware rather than the iOS or is there a glimmer of hope that iOS 4.3 will fix this for all iDevices?