IGN offers a hands-on preview of THQ's Warhammer 40,000: Squad Command, a turn-based, tactical squad combat game. I'm looking forward to this title because the gameplay is going to be incredibly similar to Microprose's X-COM: UFO Defense. I have good reason to think that THQ has done an excellent job on this title -- THQ is the publisher responsible for the Warhammer 40,000: Dawn of War series and Company of Heroes series of real-time strategy games, all of which are excellent.
Additionally, this should be a huge improvement over the PC's Warhammer 40,000: Chaos Gate, the first turn-based, tactical squad combat game set in the Warhammer 40,000 universe. While Chaos Gate isn't a bad game, it's very buggy and difficult to run under Windows XP.
I'll be getting this title for the Nintendo DS instead of the Sony PSP (in fact, I got a DS specifically because of this game) because the stylus and touch-screen are much better suited for this genre. While the PSP has better graphics, I'm more interested in the functionality that the DS offers. Looks like I made a good choice, too, because Front Mission is also going to be released for the DS -- which is another turn-based, tactical squad combat game, but instead of a squad of soldiers, Front Mission gives the player a squad of customizable war robots called "Wanzers" (walking panzer, i.e. walking tank).
Now I just have to hope that the X-COM DS homebrew project sees completion!
Update: IGN has a review for Front Mission DS.