It has been some time since I've read the book so I may have a detail wrong, but , ironically, I believe the consensus now is that the Burgess fauna are (mostly) now connected to established taxa, rather than early "lost experiments."  Hallucigenia, for example, is related to velvet worms.  All the arguments about historical contigency still hold much weight, though.

*sigh* If only Gould were still around for a new edition (among other endeavors) :-(