First of all: I love this game.
The story is superb and as a die-hard Trekkie, I can vouch that the developers' attention to detail when it comes to the Star Trek Universe is marvellous. It is the continuation of the Star Trek series and films that never was, filling up holes in the story, piecing at first glance totally unrelated episodes together and creating a story as original and Star Trek to the core as you can get. Even the "title theme" is instantly recognisable as Star Trek, while being something completely new at the same time.
The fact that a lot of known Star Trek actors (Leonard Nimoy - Spock, Tim Russ - Tuvok, Michael Dorn - Worf, etc.) lend their voices to their characters and you get to talk to them and fight alongside them makes my Trekkie heart beat a lot faster (one of the highlights for me was fighting alongside Voyager
and traveling to the Mirror Universe).
I have concentrated on the story so far as that is the most important aspect of a game to me. I am no expert in different aspects of gameplay and controls and the like, so I leave that to others. But I do enjoy that you have both ground and space fights. not to mention the diplomacy
missions, allowing me to engulf myself in RPGing in my favourite fictional universe.
So, if you are a Trekkie such as myself, this game is definitely for you. For everyone else, this is still a superb online game (stunning graphics for FTP) with an intriguing story (although you won't get all the in-jokes and references, don't worry, it's definitely not a game you can only understand after memorising each and every dialogue from all five shows and ten films - but maybe it will pieque your interest in Star Trek). I can definitely recommend it.
EDIT: Oh, if you're wondering why I have spend so little time on this game if I love it so much: I don't always play it through Steam (gaming on Linux can be a tricky thing sometimes). But believe me, I have clocked A LOT of hours on STO.