Well, I'm stretching my earlobes. Just put in 14g plugs without any trouble (didn't even need to use my taper!), and after about a month of wearing these, I'm gonna go up to 12g.
My goal is to get large enough to wear small silicone rings so I can stick regular earrings through them. I'm thinking about 8g, but I may go all the way up to 4g.