+1 on TIGHAR and their efforts: fact based scientific method based research for almost 20 years. Their next expedition, number 7, they hope to have a large enough underwater search (they may have to go down to around 1000 feet) to find one of the engines.
There is a good video, about 20 minutes long, that describes their theory:
http://vimeo.com/7715435Also, if they are right, Earhart and Noonan had to survive on the island, and possibly did so for weeks or months. Some of the artifacts they found were a broken folding pocket knife and glass bottles with partly melted bottoms, as if they had been in a fire to boil water. There is no natural fresh water on the island: they had to catch what they could from rain.
Assuming it was them on the island, the untold story of their survival and sad passing makes for some interesting thoughts on our own survival plans and what they should/could have had with them to have allowed them to survive and be rescued. Note that for at least a couple of nights, they were able to (apparently) get radio messages out that direction finding put in the area of the island . . . to no avail
Now, if we could only find the artifacts (bones, shoes, sextant box)that the British Colonial Officer collected in 1940 . . .he thought then that it was, in fact, Earhart's remains.