An argument for the authenticity of the Book of Mormon that I often hear is that Joseph Smith couldn't possibly have written it because he was an "uneducated farm boy." Maybe, but I think that anyone who has read very much of his writings can tell that he was eloquent and intelligent. I'm not saying that I think he wrote the Book of Mormon—just that his being uneducated is not a good argument against such a claim.
One of the best examples I can think of is in D&C 123:
Those do not sound like the words of a mere ignorant farm boy to me.
Another example of his talent with words is this lovely poetic statement: "But nevertheless, deep water is what I am wont to swim in" (D&C 127:2). Yet another one: "O God, where art thou? And where is the pavilion that covereth thy hiding place? How long shall thy hand be stayed, and thine eye, yea thy pure eye, behold from the eternal heavens the wrongs of thy people and of thy servants, and thine ear be penetrated with their cries?" He used figurative language well.
I could go on, but suffice it to say that I think he was a good writer and speaker. If you're going to argue for the authenticity of the Book of Mormon, don't use the argument that Smith couldn't have written it because he was some hick without a good command of English.