Burning odors can cause panic. These also have a small ballast type circuit in the base that's connected to household current so I have to wonder if they can fail in such as way as to cause a fire. My guess is they'll have a short popularity and give way to other technology such as LED.
We had a discussion last week about cell phones burning. My wife was on her cell the other day when she saw smoke and smelled a burning odor. At first she thought it was the nearby cordless landline phone so she unplugged it, but on further investigation we determined that it was the table lamp, specifically a CFL bulb. This is supposedly "normal"!
CFLs burn out differently than incandescent bulbs - the light usually dims over time and may produce a more dramatic pop, emit a burning odor, and maybe even release some smoke. CFLs with the UL Mark have been tested to meet specific requirements for electrical safety, fire and shock hazards. Any popping sounds or smoke that a consumer might see when a CFL burns out means that the bulb's end-of-life mechanism worked as it should have.
Yikes! This is acceptable?

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