At about 32 minutes in, Janeway asks Tuvok how long it has been since he lost contact with Kim, and Tuvok replies "Four or five minutes." It has been long established in the series that as a Vulcan, Tuvok speaks precisely - a comment that vague is completely out of character for him.
When Janeway is re-negotiating with the child Borg, a close up of the Captain reveals a missing pip from her neck. The missing pip was looking as if it fell off or was accidentally pulled off in a previous take.
When playing poker during the opening scene, Harry Kim claims to have 'Two Pair' and wins the round. Prior to his claim, he was clearly seen holding two Aces and three Queens making a very high Full House, which is a way better hand than a Two Pair.