I've been in a discussion of the upcoming lightbulb law with @NobleIdeas, and he's provided a blog response to my earlier post. His post is useful, since it covers most of the standard points used to support the law, as well as providing support for one of my key points. Here's my thoughts in response.
The Main Point
The federal government has many proven, existing programs to drive efficiency, including Energy Star, portfolio standards and product labeling schemes, not to mention the myriad of state and local programs, many of which have already invested in lightbulb efficiency. These are especially effective in cases where there is strong coordination with industry, as there is in the case of lighting.
Like most (all?) proponents of the law, @NobleIdeas fails to answer the following question: Given the successful track record of other efficiency programs, why it was necessary to take the unprecedented step of outlawing inefficient consumer products? Use of this new mechanism is especially troublesome in this case, where there is no cost-effective substitute on the market for specific, but common, use cases of incandescent bulbs.
@NobleIdeas provides a vivid illustration of this point in his blog post, where he has converted most of his house to CFLs, but has a specific situation in his kitchen where he still uses old, inefficient bulbs because he wants to use a dimmer. This is very similar to my house, where we've switched to more efficient bulbs, except where there's specific reasons that we can't, and where we still use incandescent bulbs.
Ultimately this comes down to a question of what you feel like the federal government's role should be in helping to drive efficiency, and whether it is a step too far to outlaw commonly used products. Personally I believe that this unprecedented step goes too far for a case where consumer health is not in immediate danger. We have already proven that we can capture most of the benefit using existing efficiency programs that will have a slower impact, but can drive to the same ultimate conclusion without outlawing products.
In short, this is an unnecessary overstep of the role of the federal government.
I'll close with one last minor comment on mercury.
One last Note on Mercury
As I covered in my recent look at state-level mercury emissions, the broader claims of mercury reduction as a result of a switch to CFLs are, on average, correct. But my issues with CFL's and mercury aren't at a national level, or even at a state level. They are at the most local level, meaning that I'm concerned about mercury spills in my house, especially in areas where the kids play and pets hang out.
Clearly the EPA has some concerns there as well, since they went to the effort to include some pretty scary directions for dealing with CFL mercury spills in their CFL-mercury FAQ.
In an effort to downplay the situation they compare the mercury released by a CFL to the mercury from a broken mercury thermometer. Personally we don't have mercury thermometers in our house (or thermostats), and certainly wouldn't have them out in any area where kids might play. Similarly, these are the areas where we have not switched to CFLs.