They come from Kirkus and Publishers Weekly. And they are good, I am happy to say.
The Kirkus Review (which, by the way, if you have a Kirkus subscription, has a major spoiler in it for an as-yet-unpublished episode, so be aware) is difficult to quote from, except for the very last bit:
A Heinlein-like adventure for a serious sci-fi fan.
I don’t mind that at all.
The Publishers Weekly review, on the other hand, is full of nice quote-y bits:
Scalzi’s hectically paced and philosophical continuation of the Old Man’s War series is an invigorating and morally complex interstellar thriller with heart… Deeply realized characters and stinging webs of political and social deceit lend mystery and emotionally harsh realism to a thrilling setting of deep space and distant worlds.
I’m pleased. Despite the fact the people had been asking me to go back into the OMW universe for a while, I was hesitant, both because I wanted to be sure I had a good enough story to tell, and because (hello, prequel trilogy) just because people want you to revisit a favorite thing doesn’t mean they’re always happy with the result. These reviews suggest I stuck this particular dismount. I think I’ll have a cookie.