Indeed, it's huge!
About those RFID tags, they have been used in the FIFA World Cup to prevent ticket counterfeiting. These tags are very cheap (in cents) and can be easily programmed to interact with a tag reader. Before going to humans, imagine the revolution in the world of inventory management: the switch from barcodes to RFID chips is the way to go ... it's guaranteed $$$.
Regarding these chips being implanted inside humans, this seems convenient. Concerning security, the only potential problem to ensure is that the data on the chip be encrypted with a specific algorithm that can only be decrypted by the reader (I'm pretty sure that's what is going now) because of the sensitive data on the chip. I don't see any other problem that is generated by this solution ... and at the same time, we can clearly see its practicality.
Speaking of science fiction, I find this conservative compared to virtual reality :) ... you can start at wikipedia, keyword: Virtual Reality. Enjoy!
