Although comparisons with Yahoo's MyBlogLog are inevitable, Explode isn't primarily intended as a way to turn an existing blog into a social network, nor as a way to monitor traffic. Instead, think of it as a loosely joined network that works on top of existing social networking sites and blogs, to allow a user of one site to 'befriend' and communicate with a user from another.
Curverider co-founder, Ben Werdmuller, says that Explode is very much a 'work in progress', and that they are already working on an API, and also have plans to add support for OpenID.
Update: More coverage over at TechCrunch