Surprisingly a shit ton of fun!
Sorry...I disagree on the 'fun' part. Don't get me wrong, though. It's an awesome game, but "fun" absolutely isn't the way I would describe it. I could talk about the reasons, but
extra creditz already did that better than I ever could.
It also puts the so-so reviews into perspective: those reviewers are looking for a fun factor and give it a low score because there isn't exactly any. However, it's a false claim. Let those same guys review a movie like Schindler's List and they'll hate it because there isn't enough "fun" in it. (you see how ridiculous that sounds? Yet somehow, for games this is perfectly acceptable behavior).
I've read the ING review and I pretty much cringed for every "bad" point it mentioned. It barely mentions the enormous amount of immersion the game gives. From the first moment to the last, you're just one lone survivor somewhere in the heart of London. You're not a hero...you're not overpowered and you're not fucking there for the FUN of it. The fact that dying turns you into a zombie which has to be killed by a new survivor is a brilliant move in that aspect: it easily reflects that all other zombies once were human too.
Oh, and perhaps for the record: I
don't especially like survival horror games. I was never a fan of resident evil (not even 4), and while I do like silent hill games, I'm not exactly following that franchise either. However, I do like a good game. And zombiu absolutely is one. It may not be everyone's idea of a pass time to have to knock pretty much every zombie on the head three or four times with a bat because ammo is scarce, it if you could knock them down with one or two hits...it just wouldn't be as scary anymore (the important part about it is that while you are fighting this one zombie, you cannot tell how many are coming up on you from other directions). Same with the scanning, looking through your backpack or turning off your flashlight to let it recharge. This game would be incredibly boring if you were given a minigun from the start and enough ammo to start world war 3. Instead, it's an awesome experience that truly gets under your skin.