I've been following Chris Breen for a number of years now and although I don't know him personally he is going to be a big loss to the readers of his work, followers of his music and podcast - like me...
I discovered Chris via the MacWorld podcast back when the iPhone launched, I picked up loads of tips and ultimately ended up choosing an iPhone and never looked back. His style in writing (and explaining things on the podcast) was always insightful and he managed to explain what was going on and never going into too much detail.
Also being a musician on the side I found Chris to be someone I looked up to even more, helping inspire me to start to write about technology, music and even writing a few podcast themes myself.
I'm really interested to see what Chris does at Apple, my best guesses are either something related to Education or the rumoured iTunes Streaming Service - maybe helping to curate the playlists or provide input to the design/UI/features.
Good luck Chris and although I am going to miss your writing and hearing you on the podcast I'm happy in the fact that I know you are at Apple and helping to improve the company we all care so much about.