While this is a pretty old concept in sci-fi it's definitely one that I've been wanting to actually live with for a while now. Even more as I've increasingly dealt with the issue of not wanting to kill animals, but not being entirely willing to stop eating meat (plus, c'mon, not to drag this further into a firestorm, but there are compelling arguments that animals killing other animals to eat is the natural way of things... nature is cruel as hell). Like others have said though, one of my biggest concerns is quality. With the way the agriculture is today flavor and quality have long, long given way to making a product that ships easily, grows quickly, reduces spoilage, and is made to conform to crazy marketing ideas (e.g. pork should be leaner to compete with chicken). All of this makes me worried that cultured meat will be dry, tasteless, and thoroughly unpleasant. A utility food for the very poor and vegetarians that's basically little more than a dry, tough tofu.
The biggest problem is that if we can culture meat with no need to kill the animals involved we really need to have human meat available. Not just for us to enjoy, but perhaps as a show of good faith to prove that it's not made from animals that have been raised for slaughter. Rudy Rucker's excellent integration of Wendy meat into his Ware series also got around one of the bigger problems to its adoption by using the oldest trick in the book: sex sells. An attractive nude woman lying on a bun with the caption "Eat Me"? Who could resist.