I heard that some people have been arrested and charged with "transmitting money without a license" for selling Bitcoins.
Does this mean it is illegal for me to sell my Bitcoins?
It all depends on the country those people are, and the laws operating there. I think they have a bitcoin-ban there, because ordinarily bitcoin is a commodity and you shouldn't need a license to sell goods unless you are dealing with illegal goods. E.g do I need a license to sell books? It depend on the laws of the land.