Since the demo site was upgraded to 2.0, formulae using the TeX filter e.g. http://demo.moodle.net/mod/page/view.php?id=924 no longer display correctly.
Thanks to Christina Russu for reporting this issue.
Assuming this issue affects all Moodle sites and not just the demo site. Sorry I've not had chance to check.
Assigning to Eloy as filters component lead in the first instance, as there doesn't seem to be a regular maths filters maintainer.