to be more specific -

i think that most people are drawn to earthships b/c of the self supporting systems - water cachement, passive solar, etc. - all of which were largely pioneered by other people. reynolds did a fairly good job synthesizing them, but i have yet to see an earthship (and i live in taos, nm, home of the earthship, and lived in an earthship here for a while) that actually meets its goals.. its almost impossible to grow food in the indoor beds b/c usually the sun is too bright and temperature varies too much, not to mention that you dont really want to grow food in untreated greywater. while his passive solar ideas go a long way, interior temp is nothing near stable, it can be waay to hot or cold depending on the sunlight. even in sunny taos, the solar pre-heat for hot water doesnt do too much - yes, you save propane over not having a backup, but with an on-demand heater use is fairly low anyhow.

the design / layout has some interesting elements and can be appealing, but overall i find most earthships fairly unattractive and poorly laid out. and the building technique itself is fairly energy intensive, both in terms of human labor (pounding those tires is hell, and every one of them needs pounding) and in terms of resources - those houses are full of cement and epdm and other materials with high resource cost. and they dont work any better than a well designed house using other materials - cal-earth's earthbag style, straw bale, etc.

my assessment is that reynolds' claim to fame is integrating all these support systems (passive solar, water, sewage, power..) into a sell-able package that has a distinctive look. but all in all, i dont think the package is really that sound, and i think its just as easy to incorporate all those elements into a house that is easier to build, less resource intensive, and still quite attractive - as distinctive or as plain-jane as you like.

of course, theres still something to learn from reynolds, and i have heard from several people that they have liked his apprenticeships and classes. i just find there is a bit of a cult of personality surrounding him and wanted to balance it with a bit of first-hand information.