Finished this last night. Definitely not the best SC. But a huge step in the right direction for a fresh start. I still felt like I was playing the entire game wrong, finding that risk vs reward wasnt in my favor when playing with stealth. You can just blaze through the game chucking grenades and executing. Using stealth mixed in just lowers the number of enemies you'll deal with. You can see this in the challenges they give you. Majority of them are requiring using your grenades, "neutralizing" people, and rarely involve sneaking around. Because of my play style, I am stuck having to grind the challenges out that I would have never done otherwise.
The end was really weak and really abrupt. There wasnt even any huge gunfight or anything. If anyone can get past that turret without getting caught in the White House near the end, I'd love to see a video. I swear I tried everything imaginable.
I also hate how they nixed a lot of stuff related to stealth. Whistling, sticky cams that whistle and pop smoke, shock stickies, dragging bodies.
The real star of the game is the co-op modes. Sooo good. Hunter > entire single player. Face-Off is actually nice too. I prefer it much more than Spies vs Mercs. Just add 2 more people and the fun really starts.
They have a GREAT foundation to start with. I feel that their next game will be their Mass Effect 2. We will really be wowed. As it is, all the delays and restarts really hurt the game in the long run, I think.