Continuity mistake: In the scene where The Bride wakes up, a mosquito is shown landing on her. The first shot of the mosquito it shows it landing with all legs. Then in the close-up shot sequence, you see the mosquito is missing a front left leg. (00:24:20)
Continuity mistake: Oren is in the back of a limo, with all six motorbikes ahead of her, after the final two have moved up from the back to the front, but when we see a shot of Oren, in the limo, there are four headlights behind the limo, the way it was before the bikes moved up.
Audio problem: When "The Bride" is cruising through downtown Tokyo, we hear the bike shift gears, but she never presses the clutch or moves the gear shift lever. (01:03:25)
Continuity mistake: In the fight scene between Gogo and The Bride, keep your eye on the ball and chain weapon. It spins in different directions depending on the shot.
Other mistake: At the end when The Bride cuts off the top of O-Ren's skull she somehow manages not to cut through the brain underneath.

Continuity mistake: When The Bride and Vernita Green are in the kitchen, Vernita mentions something like "I've got to fix my daughter's cereal." Notice when she says this, The Bride is holding her mug with the handle facing Vernita, when the shot changes, it is instantly facing The Bride - something which cannot be achieved this quickly.

Continuity mistake: In the anime sequence after O-Ren Ishii has drawn the sword out of Boss Matsumoto, the blood is splashing out of him, and up on her face. But the amount of blood on her face keeps changing. (00:40:00)
Continuity mistake: When Hanzo hands over the sword to The Bride we can see all of her hair is hanging down on her back. When it cuts a huge lump of her fringe hangs in front of her. (00:55:55)
Continuity mistake: The Bride's face gets beaten up with visible marks during the fight with O-Ren's last female fighter. But after the fight her face is back to how it looked before the fight.
Continuity mistake: The Bride raises her sword twice at the beginning of the fight with Gogo. (01:14:55)
Continuity mistake: After O-Ren chops off Tanaka's head at the Yakuza boss meeting, the position of her hand holding the sword changes. At first she is holding it with an overhand grip, then when the blood shower from Tanaka's neck ends, she lowers the sword and is gripping it underhand. (01:01:30)
Continuity mistake: When The Bride is fighting the Crazy 88s, right after it changes from black/white screen to color again, they fight in a room where the light gets shut off. Now watch close, they wait. They fight. She hits a few members of the gang. Watch the gangster in the lower left corner of your screen. He's gone. He rolls away to the left. They start fighting again. Keep paying attention to the lower left corner. You see him roll away again a few seconds later. (01:27:25)
Continuity mistake: The Bride cuts off both of Sophie's arms, but when she throws her into the hospital, she has one arm. (This mistake is only seen in the extended Japanese version of the film - in other versions only one arm is cut off).
Continuity mistake: Tanaka's severed head lands on the table and stops rolling, meaning it should stop moving. However, it then falls off the table.
Continuity mistake: In the Crazy 88 fight, when The Bride stabs a bald Crazy 88 member, at first the sword is to the left of his tie, but when we see a closeup, it's to the right of it.
Revealing mistake: In the colour version of the battle with the Crazy 88, the Bride swings herself onto the restaurant's upper story balcony. When two of the Crazy attack her and she slashes the second one, toppling him off the balcony, he is spraying water, not blood.
Suggested correction: About a minute earlier in the fight (in the extended colourized version), about a half-dozen Crazy 88 members are knocked into a fountain and get totally soaked. He's one of them. If you look, you can tell his entire body is still almost dripping wet when the bride slices him. So he's not "spraying water instead of blood." Rather, the water that's already on his body is simply splashing outward as he whips around. (It's a little confusing because the black-and-white version omits the fountain shot and tries to "cheat" the water as blood since you can't tell it's not red. But in the extended colour version, it really is just the water that's soaked him that's "spraying" outwards.)
Yeah, a plausible explanation. Except that 1) when the Crazy is running onto the balcony, none of his clothes look like they're soaked. His jacket is fluttering as he moves; whereas, if it were wet, it would be hanging down. 2) His hair, when he strikes and The Bride parries just before she hits him, is showing no shimmering of wetness before he "sprays." 3) As much water as he sprays when hit, he should be dripping with water when he comes onto the balcony, which he isn't.