Christians: Praying to the Saints Part Two?

In response to my last question most people answering seem to believe that dead Christians are alive in Heaven. One even pointed out a verse (Revelation 5:8) that seems to show saints presenting our prayers to God. They said that saints are intercessors and not mediators. What is the difference? If the saints could hear us would it be wrong to ask them to intercede for us? The Bible says there is only one mediator but couldn't there be many intercessors? Are Catholics asking the saints to be mediators or intercessors? I have always been told that Catholics worship the saints but the Catholics who answered seem to say otherwise.