As Siskel and Ebert used to say, two thumbs way up.
Desalinization for human consumption has to be one of the worst ideas ever proposed. Consider:
(1) We humans have a terrible track record for responsible resource utilization. Look at oil. 100 million years in the making, and we used up all easily accessible reserves in 100 years! Anyone ever stop to think that people living 300 years from now (if we haven't blown ourselves up) might like some of this phenomenal energy source?
(2) Example 2 (of very many), current topic, water. In the U.S., we've drawn down the aquifers underlying the Great Plains by so much that, if we were to stop tapping them today completely, they would need 500 years to refill. And this is our bread basket! The mighty Colorado River is now so completely diverted that it no longer reaches the ocean.
(3) Scientists believe that the oceans are the source of all life. We've already wiped out numerous species due to over-fishing. Dare we alter the composition of the oceans by extracting pure water and dumping back pure salt? Life in the ocean is incredibly sensitive to salinity.
Many may be tempted to say we could never extract enough water to significantly affect salinity. See points (1) and (2). If we proved that we could extract pure water from the ocean in an economic fashion, the world would quickly build desalination plants by the tens of thousands. And certainly, extraction on that scale could have a calamitous effect on ocean life.