There are several sprouting up now. I know @Dan, the creator of the steem platform, is working to create a sort of second generation steemit on the EOS platform once it goes live, and I've recently tried out Minds.com. While their token rewards system is still in testnet phase, I am very impressed with how it has surpassed steemit in sheer numbers and how in a week's time I surpassed in subscribers to what it took me 6 weeks on steem and now 12 days in nearly 13,000 views, which is probably the weakest aspect of steemit. Still steemit seems better on the blog options. Competition always plays well into the hands of the users. :)