When a foul tip occurs, the ball is alive and a strike is charged to the batter. The batter does not become a runner. If the batter had two strikes before the foul tip, he will be called out and charged with a strikeout.
A foul tip is not a foul ball, nor is it a fair ball. Many fans and sportscasters will mistakenly use the term "foul tip" when they are describing a foul ball that made slight contact with the bat or that travels straight back toward the backstop.