I'd like to collect everybody's opinion about the game right here, please do not post any spoilers as that's not needed to express an impression.
Here's mine:
Single Player:
Although I made it only one third into the game I can wholeheartly say it's an absolutely great SP experience. There is not one single dull moment or occasion where you get bored or frustrated.
The level design is very good, the proportions feel right, the world is credible (therefore immersive), the details are great and thoughtfull placed and it doesn't feel claustrophobic.
There is a nice variety of inside and outside locations - so whenever you feel like you'd want to see daylight again you'll soon reach the surface again and vice versa.
Various comments have been made about the lack of detailing in the outdoor areas and I fully support that, yet I'd like to restate that expectations often are too high. Now that we live in the world of incredibly detailed indoor levels everybody gets the natural impression that outdoors lag behind. No big deal unless you totally focus on that and decide to troll around and exaggerating it. I have no objective complaints about the outdoors, only subjective comments. Ths said one must note that outdoor textures look mighty fine albeit they lack in variety (from a nitpicky amateur custom level designer point of view).
"That ugly skybox" syndrome...
Here people definetly have a point. The skybox is absolutely gorgeous HR Giger style itself, but simply too low res - to me it's the only real letdown, yet one that doesn't make or break the game.
We should start a petition for Raven to redo the skybox as a portal sky for people like me willing to sell their home for more graphics processing power
Team Mates / NPC's:
The character design is almost flawless and the artwork absolutely adorable. You don't feel like you're interacting with the same 3 NPC's all the time but rather with a whole army.
Your team mates accompany you, the techies restore your armour and the medics your health, so it's alyways a welcome co-challenge to keep them alive as long as possible. The other squad members are really helpful in combat and pack enough damage. So you're not nursing them through the game but you really team up with them - nice touch which feels absolutely right.
They sometimes stand in your way when you retreat, but not the point where it becomes annoying.
The characters look at you, but sometimes they stare through you in a strange way - while not intended that makes them look like nervous war verteran wrecks. Somehow fitting considering the gruesome setting you're in.
Enemies / AI:
The enemies are great and the AI servies it's purpose unless you want to battle them in a chess game. The artwork and enemy detail leaves you with the desire to open up LightWave and do something on your own as a tribute to Ravens modelling skills. The skins appear a bit stretched in places, but unless you have spent countless nights pulling your hair out over UV mapping it's nothing you notice and even then you accept it without any bad feeling.
Weapons:
All fine, but the lack of recoil make the Rocket Launcher feel weak.
Again a minor complaint which falls into the nitpicky category at best.
Sounds are fine.
Atmosphere:
The game design inherits the Q2 war atmosphere and there is no occasion where you suddenly stand in a totally silent room (unless it's an intended effect). So whatever you expect to happen around you in a war scenario it constantly happens. That keeps me from standing around in boredom askig the famous "nore more level or not" question. If it were a nove I'd clearly rank it in the all-night-page-turner category.
Look and feel:
Just as it should, no ice skating.
At times your character feels a little bit too "light" - can't really explain that better. Still people with ego problems can get their fair share of mental "badassness" out of the game.
MP:
To keep it short - think Q3.
I've spent a few hours on q4dm8 (aka DM17 in Q3) and it plays just as it should. Sure it's different, but after a few matches you're "in there" again.
For myself I have made the decision that Quake4 is "it" for now.
Happy welcome back bouncepads!
Expect to see a plethora of user made MP maps in the next few months.
Edting:
Haven't poked around much in the editor, but the Q3 and D3 mapping folks will feel instantly at home.
Final personal verdict:
A must have, even if you substract the "fanboy" suspicion you might have reading a review on a dedicated id software technology site.
GG Raven and id!