Several smart-ass descriptions:
Joe Haldeman without the Vietnam War era commentary.
The Word for World is Forest without the Vietnam War commentary, dreaming, and from the wrong side of the fight.
Robert A. Heinlein without the towering Heinlein assholery.*
Babel-17 without the poetry, but with the ghosts.
Ender's Game with old guys instead of kids.
Familiar military sf with an avuncular, lightly comic bent and good flash-bang fight scenes.
A series of good ideas in search of someone to think about them, because Scalzi's not going to do it for you.
Okay, enough of that. Old Man's War
was a pretty perfect companion on the first inaugural back-porch read of the season, It's a nifty and chatty bit of military sf - or is this space opera? - same dif. The protagonist, whose name I've already forgotten, signs up for the intergalactic military at 75, which is when you're allowed to join the intergalactic military in the future. There's some interesting set up about the way Earth handles colonization and the galactic military - which is another acronym I've forgotten in the span of an evening - the new old recruits quoting the bible, putting down the racists, bantering politics, watching as earth goes to a blue orb, and then a pin-prick of light in the windows. My ears perked when the new soldiers are learning about their new hardware/avatars, the way everything was trademarked, down to the cellular level. Here comes some interesting commentary on autonomy and corporate personhood, etc, etc, and then....
....and then, well, nothing. I'm not dissing real hard here, because this was fun as a tachyon field set to stun, if you like that sort of thing, and I do. The book wears its influences on its sleeve, chapter after chapter of cool ideas that I've seen elsewhere, rattled off in a historiography of science fiction in space. Sometimes Scalzi gets close to making a point, a quick moment about the ethics of child soldiers, but then bang! bang! hardware! space battle! technojargon! bang! Sometimes this felt like setting them up and then walking away without even trying to knock them down. But then mostly I didn't care, because I was having a good time. Pew! Pewpewpew! Pew!
Richard recently accused me of liking space opera more than your average bear, and I got all huffy and claimed I did not, because I am vewy sewious. After some consideration, he's probably right - I do like it more than most. I cut my teeth on Asimov and Herbert, and I'm still trying to recapture that wide-eyed moment when their naif protagonists look out that window and see the black sky blinkered with stars, or the blue orb retreating, or the wonder of the misunderstood alien understood, or...
There are moments here, quick flashcards of my youthful reading, where I remember why it is I started crushing on science fiction - the casual ideas, the gravity-less movement, the gee-whizz - but they don't deepen to the reasons I fell in love with science fiction - the crystalline ideas, the ethics, the awe. Our protagonist loses character as he fights battle after battle, falling up within the military hierarchy with a slouching, cheerful lack of ambition. No one likes an overachiever. I can't tell if this lessening of his personality is pointed or accidental. If the first, bang up job. If the second, booooo, but thanks for the fight scenes.
*Look, I know lots of people love Heinlein, but his writing makes me itch all over my body. I suspect if I had started reading him younger...wait, this is lies. I tried and failed at 17, and while it bothers me when I can't tease out the Heinlein DNA of sf books I read because I don't have an intimate knowledge of his writing, I can't power through his writing to get that knowledge. So I can feel the Heinlein here, on the edges, and I still liked this, for full disclosure of my reading biases.