I can understand why a halogen is needed in track lights designed for small bulbs, but why would a fixture like this require them?

The product description offers no details, just lists '100 watt halogen [included]' in the description.

It's not a big deal if its a regular screw in, but I'd rather use CFLs every where I can for both the energy savings and the convenience of not having to replace them very often or stock a lot of different bulbs. If it's the tubular style halogen though, its a disqualifier for me. Hate those things!

OT, but can anyone point me to a primer for track lights in general? The different bulbs required, sizes etc. are a bit too much for me to decipher...

Here is a link that might be useful: minka 'calavera'