Just finished the game on normal.
Overall I enjoyed it, a very solid experience. A significant improvement over the previous entries - it really felt like Insomniac made a conscious effort to rectify the flaws of it's earlier work.
Graphics: The situation here is akin to what we had with Alan Wake. Woefully blurry graphics thanks to the sub-HD resolution. I would say its worse than Alan Wake, since most of that game occurred at night which went some way to mask the resolution deficiency. Theres no question Insomniac should have done better on a technical level, theres no reason this needs to be sub-HD if games like Uncharted/Killzone aren't. On the plus side no screen tearing that I could see. The art direction is fantastic, at least in the first third of the game. The weather effects - especially the wind were the highlight for me. It looked fantastic and aided in the atmosphere immensely. Lighting is generally great and the lens flare from the sniper sight was neat. I have to agree with what others have said about the character models. Apart from the main characters, they were appalling. Framerate is pretty solid from what I could gather, only dropping slightly during shitstorms.
Atmosphere: They nailed this pretty well. I couldn't help but be reminded of War of the Worlds during the campaign. The washed out color palette, the drop ships, the seemingly random horn sound effect and of course the wind effects all contributed to the vibe. While the game is not scary in the slightest, there was a prevalent sense of dread which I've never felt in other Resistance games.Half Life 2 has been mentioned too which I guess is a reference to the very Ravenholme-esque level in the middle of the campaign.
Audio: Insomniac really outdid themselves here, especially when you compare it to previous installments. The sound design is very aggressive most of the time especially in the bass. Most guns sound satisfying and the variety of actual sounds is a far cry from the generic crap we were served up in the previous two games. The soundtrack is also far better, it actually sounds unique this time and definitely something you can attribute to Resistance in future listens. There did seem to be a slight audio delay at times which is hopefully addressed in a patch.
Gameplay: The quality varied here depending on which part of the campaign you're playing. The put it plainly, any section with grims in it flat out sucked. I don't know why developers feel compelled to spam you with one type of enemy for extended periods of time ala Uncharted and Farcry. Early battle encounters are fantastic and open to your own interpretation on how to approach them. The level design is consistently good in the first half of the game. The weapons are all a blast to use - the secondary on the atomiser is great. Gunplay is a big step up for Insomniac. All the weapons feel meatier and enemies actually give some indication they are being shot. I do feel like Insomniac got lazy towards the end of the game and just decided to throw you with more and more Chimera to the point where it felt like spam. They also seemed to overuse the 'defend this point' scenario. The AI is generally pretty stupid but at least they die pretty easily so its not that noticeable.
Story: Not much to say here - does much even really happen in the second half of the time? Ending was abrupt and not satisfying at all.
8/10 for the singeplayer.
