The cost of phosphors that are used in fluorescent lamps will be increasing and this should provide some insight.
To give you some background, phosphors are a part of what is called “rare earth” metallic elements with a variety of unique properties. There are 17 groups used in such products as hard drives, fuel cells, wind turbines, polishing powders and catalytic converters. Only a few of these are used in fluorescent lamp technology.
Rare earth phosphors are found and mined throughout the world, but over 90% are produced in China. California and Australia are two other locations, but they are not in production yet. I have heard sometime in 2012. Some rare earths for the fluorescent lamp technology may come from these new facilities, but the balance will still need to come from China.
I suspect all lamp producers are working to keep the costs in check, but the time it takes to respond could be many years from now. I am not sure what the solution will be, but this provides some in-sight as to why there will be increases.
This information was taken (in part) from a article by GE Lighting.