Arianna Huffington gets a B-minus for her Twitter presence, according to this article. She follows 1,500 people and has more than 10 times as many followers. But she barely tweets twice a day and roughly 90% of her links connect back to her Huffington Post Web site. "Huffington's feed is great for people who want a peek into the life of a digital-media maven," Tameka Kee writes. "But if you're eager for a dialogue, she's probably not the person to follow."