Actually, the Wikipedia article distinguishes between “munging” (disguised addresses such as “someone at somewhere dot com”) and “transparent mangling” (using HTML entities). Disguised addresses can’t be used as links, and are harder for spambots to harvest - but can be converted into links by human readers. Mangled addresses (using HTML entity characters) do work as links, and make things a little more difficult for unsophisticated spambots.
Jeremy