What Do You Think of Tithing?
The short answer is that I am convinced that all old covenant forms are a shadow of a greater reality. For our giving that reality is described in 2 Corinthians 7-9, where we are encouraged to live in God's generosity and give of our lives accordingly, not to pay some obligation to God to appease him. Tithing was a command given to Israel as part of their covenant and temple-system. There is nothing in the New Testament that would indicate it to be binding on any other group of people and the early church certainly saw their giving in far different terms.
That said, I do think that Jesus' followers who live in abundance (which in world terms includes anyone living in a developing country) will find God's work in them will show them how to live generously with others who suffer in the world for lack of basic necessities and how to participate in sharing God's kingdom in the world through projects or people God might call them to support. Living in the reality and not the shadow means that, unless we are in a time of great need, we will find ourselves giving well over 10% wherever God might lead us. Further resources on this topic may be found in the BodyLife article, "Giving and Generosity" or one of our podcasts God, Mammon and Tithing.