It is hoped that, when it arrives, vat-grown meat will be vastly more environmentally efficient, requiring fewer resources to grow, not to mention being free of animal suffering. The current process is not vegetarian, though, using animal blood products in the growth medium.
On a tangent: earlier this year, scientists mapped the cow genome, and discovered that the genes involved in making cattle docile are in regions which, in humans, are involved in mental retardation.
to say the process is "not vegetarian" makes me want to question your definition. Of course it refers to the argument that vegetarianism is all about not wanting to be cruel to animals, but surely many (if not most) who avoid eating the stuff do so out of concern for the ill effects on themselves (ie. the happy coexistence with four-legged folk, more efficient use of farmland, less greenhouse gasses etc are all very good, but secondary to issues of "natural hygiene", to drag out the archaic term).
This is fascinating news - but putting that to one side, "A Soggy Form Of Pork" would make a great band name...