So Rigg is this country boy who hasn't seen much of city life, and he has this interesting ability whereas he can see paths left by living things, since forever ago. Turns out is a strange aspect of time traveling, which is what the story becomes about.
What makes this story unique (to me) is that... I'm not sure if I am saying this right... but in this time travel story, there is no causality to which to adhere. If he sends himself a message from the future to not do a certain thing, then he won't do it... and there is then no need to send himself that message. This has all sorts of interesting ramifications. It's not our Father's time travel story. Also, it almost feels like he got rushed or something at the end.... there is a 3-book arc, but you don't finally learn what the end game is... and it gets all wrapped up... like in the last 50 pages. Felt weird.
Anyway, it's not my fave series ever, but if you are looking for something new to read, you can do worse than this. I give it a C+, enjoyment-wise. Good sci-fi but some may be putt off by Card's ideas of morality which appear strongly throughout.
I was particularly amused by the messages from the far future which appeared inscribed on metal plates.