PETA prize should start with eggs and dairy
I have some admiration for the PETA prize for vat-grown chicken. A winner of this prize would strongly promote PETA's ethical goals, as well as many environmental goals, for the livestock industry is hugely consumptive of land, as it takes far more grain to feed animals than it takes to feed us, per calorie.
One part I admire, in a sardonic way, is the way it will make some people's heads explode. The environmental destruction of livestock, and the cruelty, are well established. However many of the people who believe that most fervently also are very suspicious of synthetic foods, especially at this level. They would never say it, but they sometimes take actions which amount to choosing the starvation of people over the introduction of GMOs in the food supply. Not that the latter does not have its risks and unanswered questions, but that the costs are so high. PETA's vat-grown chicken will cause massive debate when it comes.
But the contest is too hard (and has a 2010 deadline that seems designed to be impossible.) It requires a meat that people can't tell from chicken that matches the market price of chicken and can sell. Oddly, it doesn't require that the process be more efficient than chicken factory farms in terms of energy or land, though the cost pushes that way. But reproducing the texture and structure of chicken is a hard problem. Current work on vat-grown meat suggests less textured versions (for use in sausage and ground meat forms) will come first.
So I would propose a lesser prize, the production of vat-grown egg white, egg yolk and/or milk. As liquids, the task is probably an easier one. And these products have so many uses in foods, even if you can't make something that fries up like an egg.
Of course vegetarians (as opposed to vegans) eat eggs and diary, though the PETA variety of vegetarian will insist these products come from humane farms, with free range animals, no hormones and no forced production. The agribusiness dairy and egg farms are not this way, they will point out -- and they also consume a lot of land and generate lots of methane. And others will point out that overuse of eggs and dairy has health issues. But it's a real prize.
The other way I would make their prize more winnable (if that's their goal) would be to remove the requirement of of being indistinguishable. Instead, I would make the creation of a superior product qualify for victory. Instead of having an independent panel say "I can't believe it's not chicken," I think it would be sufficient to have them say, "This is not chicken, but I like it as much or better than chicken as a meat." And to prove this the market, where people are buying it instead of the equivalent bird. It's true that an exact duplicate would have a faster adoption curve, but the wholly new food would get there eventually if people found it tasty. Tofu is tasty but chicken eaters don't say they prefer it to chicken.
With eggs and dairy I think a perfect reproduction is more possible, in that you "just" have to duplicate the mammary tissue that produces the milk, for example. And this must be living, which may be a lot harder than the vat grown meat which may never fully be classed as living tissue. But my intuition says it will be easier, and fairly dramatic in effect.