For the past 7 years, Tchao has been General Manager of Nike's Techlab, which has been responsible for the Nike + iPod line as well as the online integration that makes nikeplus.com so powerful.
If you wanted to start doing a bit of speculating, it's interesting to note that Tchao was part of the team that was responsible for Apple's first tablet computer. Of course, the Newton platform wasn't exactly a huge success during its 5 years of life, owing primarily to its high price and (at least in the first versions) less-than-stellar handwriting recognition. Tchao wasn't in a marketing position at the time as the General Manager of Product Planning and Strategy for Apple's Personal Interactive Electronics group, and most of the marketing fumbles of the Newton era can be laid at the feet of the Apple execs in charge at the time.
Tchao certainly has the street cred as a tablet computing expert, with 5 patents to his name during his time with the Newton team. Although we don't know for sure at this time if Tchao has been tapped to resurrect tablet computing at Apple, his background both at Apple and Nike Techlab shows that he not only has the technical background to shepherd a new product to market, but the marketing savvy as well.
Welcome back, Mr. Tchao!