I know that there are various views as to what this passage is referring to, but I'm seeing something I hope will be well received. Without trying to go back to Psalm 68 where this passage originates, I would simply look at what we see here. Believers in Christ were caught in slavery to sin and thus, were captives. When Christ saves He delivers repentant sinners from this slavery and releases them to live in freedom. In this freedom Christ gives them gifts, abilities to serve Him in their new life. And this is a theme Paul introduced in verse 7.
Think about living in sin. I know, "Who wants to think about that?!" But, just ponder this thought: living in the world you possessed tendencies to do wrong which controlled your life. You really couldn't change because your nature was to follow your tendencies. You were a slave to sin and these tendencies were yours whether you like it or not! You had natural talents that you used to fulfill your lusts and basically serve the devil.
Now, being a Christian your life has changed! You have been given a new nature with new desires which cause you to want to serve the Lord. Now God has given you abilities which you can put to use in fulfilling His will. These gifts are similar to talents, but their not your "natural gifts." They are Spirit-given abilities. You will see more about what these gifts are and how they can be put to use further along in this chapter. A further more detailed study will be found in 1 Corinthians 12-14. Thank the Lord that you're not bound to sin any longer. And thank Him that you can now live your life meaningfully with new abilities for His glory!