Agreed that it's a framework, but it's not necessarily that much work, it really depends on what you're trying to do. Sometimes its easier just to use a library if it offers what you needs, other times its easier to use D3 directly -- knowing when to make that call is important.

There a good O'Reilly book on D3 by Scott Murray, the ebook version of which is free that's a great primer:

http://chimera.labs.oreilly.com/books/1230000000345/index.ht...

In my use-cases, it doesn't take much work at all. That said, it took me a fair amount of time learning enough about it (D3) for that to be true.

I think we'd probably both agree what if someone just wanted to build one (simple) interactive chart and then be done, D3 is probably not a good first choice.