Artist conception of planet orbiting a red dwarf star
According to New Scientist, an exoplanet announced earlier (discovered in 2007 with analysis appearing in 2008) located in the direction of the constellation Sagittarius may be Earth-sized.
Earlier, astronomers had estimated it as 2x-3x earth-size and of a composition like Neptune, perhaps. Now, evidence seems to show more of a 'terran' character.
Note this is different than the exoplanet optically observed around the star Fomalhaut.