(Richard Grevers lists@dramatic.co.nz):
That doesn't solve the problem of wanting to put a string of block elements within a list item (perfectly legitimate HTML)
You can still put lists inside a list item; you just can't put paragraphs or PREs. I'll have to think about how big a problem that is, if any.
It's certainly /not/ my intention for wikitext to be able to represent any possible DOM--just the most useful, powerful subset that keeps it simple enough for newcomers to edit.