According to the article, this is just a pill that you swallow, and when it hits the stomach, it transmits the time. Then later it gets pooped out.

So it's not "implantable", it's not "implanted", it doesn't "track you", it doesn't "store information". It's not "the mark of the beast". It doesn't make sense to be terrified of some device that will help doctors do their jobs, and can't be used for any of the fear-mongering ascribed to it.