I kinda do see the potential in [name_m]Seth[/name_m] being borne by a girl / woman. I saw [name_f]Shannon[/name_f] on males, same with [name_f]Meredith[/name_f]. Why not [name_m]Seth[/name_m] as well?
I do not, however, see myself naming a daughter [name_m]Seth[/name_m], either.
Would actually make for an uber-cool nickname for [name_f]Merida[/name_f].