Hey,
>>2 here.
Actually the Japanese wrote papers on it, some American guy actually managed to cultivate some though. The yield from the truffle crop was, is (and is for the foreseeable future) very very low. The costs for the amount grown put them pretty much at the same price as the wild truffles (sometimes at a higher rate) Though it's only french Black Truffles that they've done.
>>5
Some people say it's heaven. Other people say it tastes like dirt. =/ The flavour is rather strong, earthy. And well of course Mushroomy... I didn't like them the first time I had them. BUT they grow on you, like most fungi do.