Good stuff from Steve Manskar:
The "image of God" means that human character is a reflection of God's character. We are not exact replicas of God, but we are representations or likenesses of God. This means that human beings are relational creatures. God created us with the capacity to give and receive love. We are made for relationship with God, one another, and creation.
This doctrine tells us that God's nature is revealed in the relationships within the Trinity: the Father loves the Son; the Son loves the Father; the Holy Spirit proceeds from the love of the Father and Son. Each person is unique in character and work. At the same time each person participates in the life and work of the others. The Three are One, united in and by love.
You can read Steve's entire post here.