Some of the comments in the thread above make me fear for the future of the human race if there are posters out there who can write and use computers but can't, for example, figure out why the Martians in the film are dying when the narrator actually explicitly states it at the end of the film :crikey:!
I agree with the majority of those who have taken the tack that, whilst it is not a film-of-the-book but a remake of the earlier War of the Worlds, it is still a pretty good watch.
I was particularly disposed to scorn and despise it as I chose H.G. Wells as my English Literature dissertation way back when we still had to learn things in school {pauses to push that particular soapbox away before I get going

}. So, I was therefore surprised that, despite the inconsistencies here and there and the liberties with the story, it was quite emotionally engaging.
The feelings of fear and helplessness and impotent rage (particularly around the Ferry scene when the Tripods are striding over the hillsides randomly slaughtering/harvesting the fleeing population) were very well put across. The all too human frailties of the main characters worked well too. Even the screaming daughter with her multiple modern-day allergies and weaknesses that rapidly became secondary when everything fell apart.
The greatest let-down, as others have said, is the unexplained survival and journey of the son. A few scenes that hinted at how he evaded incineration would've been welcome but you can always use your own imagination to fill in the blanks I suppose.
I would recommend anyone to go and read some of the H.G. Wells classics. He was a great 'futurist' and scientific thinker; one of the Great Minds of the 19th century. Some of his novels seem a bit pedestrian and predictible now but you have to remember that the things he was writing of hadn't even been invented (and some still haven't). So don't be so quick to dismiss certain elements of his work just because a hundred years of advancement for us have revealed a wider horizon.