However, it seems like a waste of resources if everyone is trying to set up and maintain their own blog, and especially the debating software.

So, the thing that I think most exciting here would be some sort of LW comment API / easy WordPress plugin / whatever, so that one can trivially add LW commenting to their blog, and people can have one shared account and comment response inbox across all rationalist blogs.

How could we better encourage the creation of the taskforces? Do we even have them, explicitly?

So, I think one component of it being a "taskforce" instead of just a blog is that actual work is getting done. Yes, there's stuff like IAFF that's primarily discussion--because that discussion is leading to papers and constitutes "actual work." But CFAR seems like it falls into the 'task force' category--it has a mission, but also employees, a budget, and so on.

And I think it makes sense to treat LW as a "forum," in the ancient Roman sense. You'll talk about your business in the marketplace and keep abreast of what's going on elsewhere, but it's not a good place to try to get your work done--that's what your own building is for.