Thanks for the comments, folks! Here’s a revised version, a little more separation and emphasis in the blur FX, and a slightly different color treatment. This is what I plan to use for the final effect, though not with this animation – I’m just using some I already have done for Act 1 to develop the look:
The semi-random blobs of light surrounding her, apart from the aura, are a “tattered” cloth object also run through a set of Blur nodes, then recombined with the rest further down the pipeline.
@ blenderman345 – Since it’s a post-production 2D effect, no reason this can’t be used with any subject, even from live-action vids, as long as there’s some way to isolate the subject you want to have blurred. With vid, you’d either have to shoot some sort of blue- or green-screen equivalent that lets you pull a clean matte, or do some rotoscoping.