[Petronski]

Last I saw these new bulb also wont work with a dimmer switch or motion light so I guess plenty of switches and fixtures will need to be replaced.

There are versions of the fluorescent bulb that are dimmable.

[Don Joe]

There are versions of the fluorescent bulb that are dimmable.

Sort of. In a manner of speaking.

What there is, is a dimmable ballast. It is NOT "socket-compatible" with an incandescent bulb using a normal light dimmer. It's a special ballast, with a proprietary dimmer control. It's NOT something you can use to replace a bulb in a dimmer-controled socket (and that includes nearly all X10 stuff).