Visible crew/equipment: During the ferry disaster, while Ray, Robbie and Rachel are in the water, when the car heads toward them a vertical cable is visible at the left side of the car, beside the side view mirror. (01:03:30)
Visible crew/equipment: After the ferry disaster, and close call with the car, the trio are underwater swimming up towards the surface. When Robbie turns his head to the side the regulator in his mouth is visible. (01:03:45)
Continuity mistake: After the ferry disaster, the trio swim to shore and climb up the bank. In the side shot Ray holds Rachel's left arm and Robbie holds her right arm. However, in the next back shot Ray holds Rachel's right arm, and Robbie holds her left. (01:05:00)
Continuity mistake: While the aliens rummage through Ogilvy's cellar, Ray and Ogilvy have a tense, silent tug-of-war with Ogilvy's gun, and their arm and hand positions differ between consecutive shots. (01:27:15)
Visible crew/equipment: When Ray and Ogilvy play tug-of-war with the gun, as the aliens rummage around the cellar, Ogilvy finally pulls it away from Ray. In the next close-up of Ogilvy and his gun, the boom mic dips down for a moment, but it's gone in Ogilvy's next close-up. (01:28:15)
Continuity mistake: In Ogilvy's cellar, in the close-up of Ray's hand, he holds it up to the red mist blowing through the two broken windows. In the next shot however, as Ray looks at his hand and realizes it's blood, the right window is suddenly blocked with a broken shutter and two pieces of wood. (01:29:15)
Continuity mistake: When Ogilvy shouts, "Ray! Ray! Ray..." in his cellar, Ray runs to him and there's blood splattered all over Ogilvy's face, but in the next shot the amount and pattern of the blood differs. (01:29:30)
Continuity mistake: When Ogilvy shouts Ray's name half a dozen times, Ray runs to him to quiet him down. The broken cellar window behind Ogilvy has shards of glass and red roots growing on it. Then in the next exterior shot, the shards of bloody glass are different size and shape, and the roots differ as well. (01:29:35)
Continuity mistake: When Ray tries to quiet Ogilvy, and then decides to kill him, the pattern and size of the sweat stain on Ray's shirt differs repeatedly in the following shots. (01:30:45)
Continuity mistake: When Ray places the blindfold on Rachel's eyes, while in Ogilvy's cellar, its position and folds differ in consecutive shots. (01:31:40)
Continuity mistake: In the scene right after Ray kills Ogilvy, Rachel finishes singing her song and as she's taking off her blindfold you can see that her hair is all messy and dry. In the very next shot her hair is all wet and neat. (01:33:00)
Audio problem: After Ogilvy is dead, when the alien snakelike giant eye surprises Rachel she begins screaming. As Ray hacks away at it with an axe, she stands at the wall screaming, and when the last long scream is heard, her mouth is closed just before Rachel runs to the stairs. (01:34:30)
Continuity mistake: Ray leaves Ogilvy's house to search for Rachel and soon runs into the pickup truck, just before the tripod's tentacle lifts it. The massive red roots growing all over the pickup are very different in the next shot, as it's lifted in the air. (01:36:20)
Continuity mistake: When the tripod tosses the pickup truck, with Ray in it, it lands upside down and the windshield shatters. The size, shape, and characteristics of the hole and breakage greatly differ between shots. (01:36:25)
Continuity mistake: Whilst Ray is trapped in the upside down pickup, he looks through the windshield hole directly at Rachel, who stands on higher ground. In the next shot from behind Rachel, the landscape, wood fence, etc., to her sides are entirely different from the previous shot. (01:36:35)
Continuity mistake: As the tripod is attempting to have Ray sucked up, the soldier begins pulling Ray's arm down, trying to free him while he himself is being raised in the air. In the following shots, Ray's rescue is shown from three different angles, and each angle is distinctly different from the others. (01:40:00)
Continuity mistake: While up in the tripod's "holding cell" for humans, Ray spits the circular grenade pins into his hand, and their positions on his palm differ between the two consecutive close-ups. (01:40:15)
Continuity mistake: In Boston, when Ray breaks off a piece of the dried up root from the statue, the piece he holds in the next shot is completely different. (01:41:35)
Continuity mistake: In Boston, Ray and Rachel discover dead red weed on a statue. If you look behind them, you can see a space between two buildings that is clear, only sky. In the next shot, when the crashed tripod is being shown, the spot where there was just sky now has the tripod legs. Compositors forgot to add the tripod in the previous shot. (01:41:55)
Audio problem: In Boston, just after the military destroyed the tripod, in the tunnel Ray holds Rachel and we hear him say, "I love you. It's ok. It'll be ok," but his lips really say, "I love you. It'll be ok. It'll be ok." (01:45:10)
Answer: They're reported to be about 100 feet tall.
Which is about 30.5 meters.
lionhead
They definitely seemed a lot taller than 100ft in the movies though that's for sure. I would have guessed maybe a few hundred feet.