Yeah, Steemit and Busy are the main two frontends for the Steem blockchain but they have a lot of copycats. Dlive and Dtube are considered frontends to, but they only show certain content. SteemPeak shows a lot of promise in that it's already at the level of Busy and the creators plan to make it even better with a number of updates this month.
One of the awesome things about Steem is that anybody can build a website on top of it. You can build something like SteemPeak which lets you see everything on the blockchain, something like GoodBook Reviews that lets you write book reviews, or something like Finally Comments that lets you use Steem for comments on your blog. The possibilities are endless. I'd personally like to try making a stock image site on the Steem blockchain someday.