I am convinced that John Scalzi is channeling both Robert Heinlein and Joe Haldeman (and let's ignore the fact that Haldeman is still alive). Strongly reminiscent of both Starship Troopers and The Forever War, but plenty original enough to stand on its own.

A continuation of the Heinlein/Haldeman homage, not quite as good as Old Man's War, but still quite excellent. Follows a different character than the first book, but continues the story of the green soldiers :-)

Third book of the trilogy (ok, there is actually a fourth book now, Zoe's Tale, but it was a trilogy when I read it :-) Continues the story of John, Jane, and Zoe, as well as assorted aliens, a new space colony, and a galactic conspiracy to destroy humanity. Continues Scalzi's tradition of excellence.

Reads a lot like a Heinlein juvenile — four kids and a spaceship they built themselves, along with the obligatory eccentric adults (washed up astronaut and his brilliant but wacky brother) travel to Mars to rescue the U.S. space program. It's not so much that the plot is believable, but that the characters are great, and the book is fun to read.

The story of Manny and his friends set partially on Mars, and partially on Florida, in the aftermath of a tsunami. As with the first book, it isn't so much about the plot, but the description of a colony on Mars on the one hand, and the effects of a tsunami on the U.S on the other, are believable and interesting.

A continuation of the previous two books, centering around the next generation. Still worth reading, although not as good as the first two, and beware, this one partially switches to channeling later Heinlein, which for the uninformed, implies somewhat of an obsession with sex :-)