Warning this post has some serious spoilers.
Skyfall: Before I begin in the interest of full disclosure I should say that I am a huge Bond fan. But less you think that means I will somehow be unable to impartial and/or to critique the film, have no fear. I have left Bond films before so disappointed I was close to demanding my money back or at the least wanting to give someone a good talking to. 
I was thrilled when Casino Royale was made and they decided to change the Bond movies from a self mocking, low brow waste of time, more worried about cramming as much advertising, locations, retarded gadgets and skin as possible than about making a movie that made any sense whatsoever  into a more serious movie. Not serious as in Schindler's List, but serious as in we're telling a story. Sure it's an action story, but it has a plot and everyone is acting their part and none of those parts are intended to be comedic relief.
Anyway, this review is about Skyfall and not Casino Royale.
I had a few problems with the movie. 
Let's start with the Excavator on the train. What exactly was he going to do with it? Was he planning on slamming the bucket into the bad guy? Because while they didn't exactly say that he was a super genius, I don't think he would have just stood there and watched it hit him. Excavators don't exactly move at lightning speed. Also they have limited reach. Here's my idea of what would have happened.
Bad Guy sees excavator moving at him at max speed. 
Bad Guy thinks to himself: Is he seriously trying to hit me with that?
Bad Guy spends some time pondering his career choices and whether this is worth it.
Bad Guy reminds himself that Bond has run out of bullets and thrown his gun away.
Bad Guy reminds himself that he has already shot Bond in the shoulder and thus Bond is hurt.
Bad Guy spends some more time wondering about career.
Bad Guy scratches itch.
Bad Guy takes two steps back out of range and either waits for Bond to get out of cab of excavator or simply walks away.
But instead the script had him shoot the coupling between cars. Another option. But perhaps not the best.
Another problem was the whole point of Silva's plot. It seems to me the thing he wanted to do most of all was to kill M. So why didn't he just do that?
Why exactly did he need to set everything up so that he could get arrested and get the British Secret Service to move their base into the underground bunkers? As far as I can tell the answer was so that he could then escape and kill M. This all could have been achieved much more simply. He could have simply waited for M to actually get back to her office and then blown her to kingdom come.
But he wanted to talk to her face to face and then shoot her, you reply. Okay, then he could have come to London and shot M in her house. It doesn't seem like that would have been to hard. Bond broke in no problem.
Also, how and why exactly did he blow a hole in the ceiling so that the subway could fall in and not really come close to killing Bond? When exactly did he have the time to set up those explosives? And assuming we can get past that problem, why did he do it? Or rather how did he know that Bond (or anyone for that matter) would be chasing him and catch up to him at that exactly place and time. And that there would be a train coming by at that point. And as previously stated, it didn't really succeed in doing anything. Bond took the tactic Bad Guy in the train scene should have. He just stepped to the side.  If Silva actually knew Bond (or whoever) was going to be there at that time, then he should have put the bomb where it would have exploded and killed Bond (or whoever).
Anyway, there are a couple of other things like this that strained the bounds of contrivances and made Occam's razor rusty,  but let's move past that.
I still liked the movie. I am fully prepared to admit that that fact is probably because I like me some Bond movies, but whatever. I do disagree with some articles I read about the film that said it was the best Bond movie ever. Casino Royale was easily far superior (imho). But it was other engaging and fun.
Perhaps the thing I like most about it is how it managed to both continue the Bond mythos on it's already set path at the same time it managed to reboot it as well.
They brought back a car from an old film linking this one to the past at the same time they introduced a new Moneypenny as if she was there for the first time. And there's once more a stuffy British dude sitting in the red chair and if his mode and manner are very similar to the man who used to sit there so much the better.
 - For instance, Die Another Day was aptly named, because anyone who watched it died a little bit that day.
 - But then I already talked about Die Another Day.
 - Betcha didn't see that one coming.
 - Something roughly in the neighborhood of 3 m.p.h.
 - Okay jumped, but the train was actually moving fast, as opposed to the excavator bucket.
 - Like even a first year agent knows you don't hook a strange computer up to your network. Nevermind somebody who's supposed to be a computer maestro.