Recent books:
"Star Trek: Titan -- Over a Torrent Sea" by Christopher L. Bennett
Bennett tries to mix action with worldbuilding and cool alien cultures and usually succeeds at doing both, but they rarely mix well together. Still, he really is good at characterizations of the Titan crew. However, this book has way too much forced sex (that is, the sex scenes feel forced, not that the characters are having non-consensual sex, because that doesn't happen in the book). The whole minor arc where Lavena tries to figure out if Riker could handle living alone on the planet with her is really uncomfortable and weird. Good but not great.
"Star Trek: New Frontier -- Treason" by Peter David
Another strong entry in the NF series, though not a good book for a newcomer. You really have to know about the characters to appreciate the nuances. Plus, David has been given free reign by Pocket to do his own thing, and so while the Typhon Pact is going on in the rest of the universe, he's created his own super-bad-guys. Lots of action, some funny stuff, story arcs building to keep you interested in the next book, a MAJOR character death (done very well), and a great pace -- David is excellent at pacing. But the book was not one of the best in the series. Still, it's better than a lot of other Trek fiction.
"Medicus and the Disappearing Dancing Girls" by R.S. Downie
This is an almost-doorstop that I'm still reading. I'm not sure exactly when it takes place -- Hadrian is mentioned, but so are the Crusades. It's about Romans occupying a city in London, and one of the doctors who works at the army fort. Funny, good descriptions, but the first couple hundred pages don't move very quickly. I like the character of Ruso, the protagonist, but it seems like TOO much bad stuff has happened to him -- sitcom-esque, almost. I've got another 250-300 pages to go, and I'm hoping we finally get some payoff with all these plot threads the author's leaving laying around on the floor. If you can make it through the first 75 pages you'll keep reading.