Although the science (especially where temperature was concerned) was quite dodgy, this was a very good movie. I hope the governments of the world take note, but I doubt they will pay attention as it is a fairly radical and sensationalistic representation of a possible future. The effects were most impressive, apart from the wolves, which seemed to be developed on outdated cgi models for all aspects (movement, muscle interplay, fur movement, etc). I don't think they added anything to the story and probably would have been better left out.
The most unbelievable aspect of the movie was the snap freezing in the eye of the storm. With no air movement, everything completely snap froze from the top down - ground level was last to freeze. The explanation put forward was the supercooled air from the top of the atmosphere was flowing downwards, causing a temperature drop of 10 degrees per second (IIRC). However, I did love the water effects through the streets of New York (although I don't think those buildings would have withstood such flooding).
There is a novelisation available by Whitley Strieber, which has received mixed reviews. I am unlikely to read it as I have found that novelisations tend to lack the depth implied by the movies, by good acting, good soundtracks and scenery. You need a very experienced author who is capable of writing with depth of description, expansion of story and character and extreme clarity to achieve a good novel based on a movie.
A neat movie, with believable acting, a good but not overly memorable score by Harald Kloser, and decent effects. Even though there were some horribly flashing lightning scenes, I did not get a headache (possibly as I saw it in a smaller cinema, which is typically not as completely dark as places like Village and Hoyts). I hope many people see the movie, and are encouraged to look after the environment more than they currently do.