I should add the March Upcountry novels (March to the Sea, March to the Stars, and We Few) by David Weber and John Ringo. They are good solid military SF, although the battle scenes get pretty repetitive after a while.
There are an entire slew of writers that all write very similar military SF/F and all seem to write books with each other: David Weber, John Ringo, David Drake, Robert Asprin (while he was alive), Mercedes Lackey, Eric Flint, plus a few others. A large portion of their stuff is good but it shares the Excessive Combat Descriptions problem. Eric Flint's 1632 is top notch and he's turning it into a series, unfortunately he started some sort of big web forum community so the books increasingly read like they were written by a committee.
The Deed of Paksenarrion (three books) by Elizabeth Moon is very good.
I recently read two of Lois McMaster Bujold's books and I enjoyed them, but my recommendation of her Miles Vorkosigan stuff is only partial because I only read those two.
If you like dark (i.e. slightly erotic) fantasy then the Black Jewels trilogy by Anne Bishop is highly enjoyable. However it's quite feminine.