I've never understood this obsession. Odds are you've never heard of Ceres, but it was once called a planet. It's now considered a dwarf planet, like Pluto. Pluto is also less massive than Eris, so if you include Pluto you should also include Eris. None of these have cleared their orbit though.
I understand it's frequently just a joke, but it's always rubbed me weird because some people actually became science skeptics because "suddenly Pluto isn't a planet" or whatever. Really the reason is because the list would get really long if we included everything.
Earth like? No. They're too small to hold any reasonable atmosphere. That doesn't rule out life, but it's unlikely. They're also likely too small to have subsurface oceans or things like that without being tied to a planet and having strong tidal forces squishing it, in which case it'd be a moon not a dwarf planet.