After copying the templates to a new theme and enabling the new theme, have you tried "flushing" theme registry and other caches? If you install Admin Menu module, you'll find "flush all" on the extreme top left of your site.
Flushed everything. Repeatedly in fact. :)
You can also go into "admin/build/views", find the relevant views, and for each display type ('page', 'block' etc), go to information -> scan template files. Don't forget to save. For a good measure, flush all caches after that. And log out and log in.
Tried that too. Nothing helps. :(
Thanks.