I didn't know there was a Formic Wars series. I've probably read a dozen Enderverse books.
Mazer Rackham is baller. I hope they made him badass in the prequels.
The correct name for the series is "The First Formic War". Books #1(Earth Unaware) and #2(Earth Afire) are copyright 2012 and 2013. So, I guess they were not on the bestseller list if you have not hear of them.
Mazer Rackham is a serious badass in these books. No spoilers here :-)
The other cool part of this series is the description of families of Kiuper Belt miners. These are clans of people, mostly from the same region of earth (e.g Venezuela or Italy). Their customs and how they make sure that the do not in-breed, their trading and their ships all make for fascinating reading.
Overall, if you ever read the Enders game series and wondered how and when this conflict started, these would be good books to read.