It's already been said about as well as I could. I don't completely agree with him -- but Marc MacYoung has covered it pretty well HERE. You'll also find something of relevance at Budo Blog and this post as well. These are just fresh in my mind. There are plenty of others.
Note, please, that I that I thought I made it pretty clear that some arts will give you functional skills more rapidly than others. By logical extension, some arts are more immediately functional or applicable than others. Some arts are a whole lot closer to their combative roots than others... and some live deep in fantasy land. (Rod Sacharnoski's Combat Ki stuff leaps to my mind... along with Dillman's no touch stuff... and lots of others.) But that doesn't mean that someone who trains in those arts with an attitude and emphasis on actual application for real violence can't use them effectively.
Note, please, that I that I thought I made it pretty clear that some arts will give you functional skills more rapidly than others. By logical extension, some arts are more immediately functional or applicable than others. Some arts are a whole lot closer to their combative roots than others... and some live deep in fantasy land. (Rod Sacharnoski's Combat Ki stuff leaps to my mind... along with Dillman's no touch stuff... and lots of others.) But that doesn't mean that someone who trains in those arts with an attitude and emphasis on actual application for real violence can't use them effectively.