Caleb Crain, a NY Times columnist, decries the use of CamelCase (via daringfireball). The basic argument comes down to:
Word spaces should not be taken for granted. Ancient Greek, the first alphabet to feature vowels, could be deciphered without word spaces if you sounded it out, and did without them. Spaces or centered points divide words on early Roman monuments, but Latin, too, ceased to separate words by the second century. The loss is puzzling, because the eye has to work much harder to read unseparated text.
While I don’t particularly wish to leap to the defense of CamelCase, all the arguments the writer raises against it are either matters of taste or predate the advent of lowercase. The whole point of CamelCase is that word boundaries are made clear via capitalization (instead of spacing). If the writer were able to summon up a utilitarian argument — e.g. evidence that it’s harder to visually parse “CamelCase” than “camel case” — then perhaps his arguments might hold more weight. I think it’s pretty hard to argue in favor of “I pod” or “I. pod” over “iPod” on the grounds of aesthetics or readability.