Well, Lucy, I don't expect much from Spielberg films except big, bloated, sappy, melodrama--occasionally overburdened (as in this film) with technological gimmickry and special effects to the point of distraction. But all kidding aside, here are some point by point problems with the film, IMHO:
First, I could begin with questioning the wisdom of digging up this Victorian xenophobic fossil as a narrative for a film project in the first place. Orson's unique re-visioning of the original H.G. Wells story aside, the original WOTW is actually considered a fairly primitive and unsophisticated work of alien invasion science fiction. It was, I understand, a product of the imaginations of its time and should be respected in that context. But as a jumping off point, Speilberg had nowhere to go with his narrative but to fill it with all of the dopey extraneous and completely absurd plot elements that litter this mess. And I don't think the parallels to the realities of 911 were clever or insighftul, either visually or metaphorically.
On to visual style. Glenn is absolutely correct when he cites the problems with the CGI in this film. Complete breakdown in continuity and a total distraction from the narrative flow. Contrast the scenes involving conventional real-life scenarios and its even more painful--the cinematography and production design is TERRIBLE. Look at the sequence in the underground bunker with Robbins: where are the light sources coming from, for god's sakes! It looks like the lighting set-up in a bad student film! And don't even get me started on the incredibly cheapo set design work--that "red weed" set piece that Cruise stumbles out on to is only the worst example. Another thing I notice in particular is editing and the cutting in the film throughout was just plain clunky. I mean, I literally noticed myself several times saying, "Ouch, that was a painful cut!" And the list goes on and on.
While it can be assumed that Spielberg has more auteurist control over the total vision of his films than other directors, the one thing that he absolutely has control over is the performance of his actors. He had some good people to work with here, Cruise included, who could cry nicely on cue. But the direction of character interaction was stiff, awkward, and frankly unbelievable at times. I actually felt creepy whenever Cruise and that actor playing the son interacted in any way. And not just at the beginning when it was supposed to be uncomfortable, but at the end too--I just burst out laughing when the kid appeared and went to hug his old man in the middle of the street. Duh. Way to go Stevie!
I've got to stop, but those are a few of my very personal gripes with the film. As I've said earlier, I actually like a couple of Spielberg's films, but this is certainly not one of them.