For those who aren't familiar, Mark Bittman is kind of a foodie god; I'm pretty sure organic wheat springs up under his feet when he walks around. Here's the part of Bittman's article about the fake chicken, from back in March (linked from the Slate article):
... at least one new product is a better-than-adequate substitute for chicken in things like wraps, salads and sauces. I know this because Ethan Brown, an owner of Savage River Farms, came to my house and fooled me badly in a blind tasting. (A pan-European “LikeMeat” project appears to be making progress on a similar product, and others are in the works.)
On its own, Brown’s “chicken” — produced to mimic boneless, skinless breast — looks like a decent imitation, and the way it shreds is amazing. It doesn’t taste much like chicken, but since most white meat chicken doesn’t taste like much anyway, that’s hardly a problem; both are about texture, chew and the ingredients you put on them or combine with them. When you take Brown’s product, cut it up and combine it with, say, chopped tomato and lettuce and mayonnaise with some seasoning in it, and wrap it in a burrito, you won’t know the difference between that and chicken. I didn’t, at least, and this is the kind of thing I do for a living. Brown does not see his product as a trendy meat replacement for vegans but one with more widespread use. (His production is at an early stage, but Whole Foods is planning to start using his products in prepared food soon. Retail sales of his “chicken,” which does not yet have a trademarked name, are expected to begin this summer.)
http://www.nytimes.com/2012/03/11/opinion/sunday/finally-fak...
So it sounds like this is a complete substitute in dishes where you chop up the chicken and add strong flavors, and not really intended to be a substitute otherwise. It's not 90% of the way there in all dishes -- it's 100% of the way there in 75% of dishes. And it's cheaper and takes probably a quarter of the resources to produce. Given the size of the total market, that's a huge deal.