What with Scott Moore, George Kliavkoff and, today, George Bush, it’s a week of departures. Add to that list Tony Fadell, SVP of Apple’s iPod division (bio). He is leaving for personal reasons and will be replaced this month by IBM microprocessor technology development VP Mark Papermaster, a source told WSJ.com. In response, IBM is now suing Papermaster under his non-compete contract clause, to prevent him from divulging secrets about its microchips, News.com says.

Fadell (pictured), who reports directly to Steve Jobs, is certainly one of the fathers of the iPod. After working on the idea for his own startup Fuse, he shopped it to RealNetworks (NSDQ: RNWK) before joining Apple (NSDQ: AAPL) in 2001; he then replaced retiring Jon Rubenstein as SVP in 2006. There’s speculation Apple wants Papermaster to lead development of a new range of chips for its music players, though the growing lineup of OS X devices (Apple TV, Mac mini, iPhone) may also necessitate chip design for a range of new boxes.

• Industry Moves: Apple Names A New iPod Chief and a COO