Here is an interesting re-cap of the issues:
"There seems to be more confusion than there should be over causes of action against lawyers for breach of fiduciary duty. A recent complaint (Download irell0409.pdf) by Charter Communications against Irell & Manella exemplifies the tendency of malpractice plaintiffs to plead breach of fiduciary duty claims as well, based on much the same conduct and claiming the same damages.
A recent opinion requiring the Wilson, Elser firm to disgorge over over $3 million in fees (see story here) pointed me to a very fine article on the subject by Chuck Wolfram. I largely agree with what I see as his conclusion–that courts should not recognize as independent causes of action breach of fiduciary duty claims that do no more than re-hash malpractice claims, seeking the same relief based on the same facts–though I think of it in a slightly different way. (NY and Illinois courts follow this approach; California does not, so far as I know). "