nope It won't be much use to you all filtered through my brain--I've only dabbled in programming. The most interesting bit I took away was that the were able to put the engine onto the iPhone 3GS (required) 90% intact as C++ code. The remaining 10% is the platform-specific Objective-C that interacts with the engine.
The engine was shown briefly running on an iPhone 3GS and it looked great. It doesn't run at 30fps yet, but using some creative shader techniques, Epic was able to preserve much of the look of UE3 while shrinking it down to Apple's latest and greatest iPhone.