I've played through the campaign on normal and classic and feel I've got a handle on the game as a whole.....

User Rating: 8.5 | XCOM: Enemy Unknown PC
...and while I am pleased with the "re-imagining" and find it almost as challenging as the original, I find that I am a little disappointed by the lack of depth. I feel that this was a missed opportunity for Firaxis in that there is just not very much in the way of content or game play. Specifically the tech tree feels to limited and you get the sense that it could have really been robust and more rewarding. The campaign is extremely short even though, to be fair, the maps take quite some time to go through but that is how this plays and not because there is so many missions to experience. The balance is a little off to in many small ways. I found the SHIV's completely useless and did not use them at all and the psionics appeared way too late in the campaign and so are a missed opportunity for enhancing the game play. I really hope they put out an expansion with a lot of content and game tweaks as I really enjoyed the first 2 playthroughs but now am bored with a game I should be able to replay a lot.