DUB versus SUB: Which is superior?

"Samurai Champloo" - Example
of good English dubbing

It's the age-old question... Ok, maybe it's not quite that epic, but it's definitely been debated since anime began its migration from East to West.

Obviously, most Americans do not speak Japanese.  Thus, the dilemma arises when distribution companies must decide how to market their product to American viewers.  Do you leave it as is, with the addition of subtitles (Henceforth referred to as "sub")?  Or, do you hire a whole cast of voice actors to perform the anime in English (Henceforth called "dub")?  Here are the pros and cons of each.