When I was doing my PhD, more than ten years ago now, I remember coming across a peer reviewed article which had a drawing of a PDA (personal digital assistant) positioned graphically "in" the upper arm (just below the shoulder). The PDA was supposed to be embedded, just like this temperature sensor with bluetooth capability.

I would suggest for anyone thinking this is "awesome" that they take a good long read of the following article: 

Amal Graafstra, K. Michael, and M.G. Michael. "Social-Technical Issues Facing the Humancentric RFID Implantee Sub-culture through the Eyes of Amal Graafstra", IEEE International Symposium on Technology and Society,  Ed. Katina Michael. Wollongong, NSW, Australia: IEEE, 2010. 498-516. Available at: http://works.bepress.com/kmichael/193 

I would also suggest going against the kind of procedure that was advocated- infection CAN kill you if neglected!