Other mistake: When Obi-Wan first arrives on Kamino, someone else is sitting in his Jedi fighter. Wrong hair - you can even see a different face and different skin tone. (00:41:08)
Revealing mistake: There's a shot showing Anakin from below after Obi-Wan says ""I hate it when he does that." Some vehicles appear out of nowhere in the sky as he goes down. (00:19:19)
Continuity mistake: When Padmé is getting in the last gunship Ki-Adi-Mundi's lightsaber changes from blue to green.
Suggested correction: His lightsaber is always blue, although he does help Kit Fisto board the gunship. For a moment, it could look like Kit Fisto's green lightsaber blade is coming from Ki Adi Mundi's hand.
Continuity mistake: After Padme shoots the Geonosians off the chariot, we see a shot of Anakin slicing down come droids. When he turns his body around to face the camera, we can see that he is using the incorrect lightsaber hilt, instead using what looks to be the one that is broken in the factory earlier in the film, judging by the black grips on it. (01:51:30)
Suggested correction: The lightsaber he is using was given to him by other Jedi, they threw one each to him and Ben so I doubt very much it is that particular lightsaber from earlier.
Visible crew/equipment: When Obi-Wan is on Kamino, and he first meets Jango Fett, you can see the camera in a shiny black window frame. (00:51:10)