When hovering over the "Community wiki" tooltip for a CW post from the home page, or questions page, e.g. this page, it shows
This post is community owned as of Jan 1, 0001 at 0:00. Votes do not generate reputation, and it can be edited by users with 100 rep
which is clearly incorrect. All CW posts show this same information. Other sites, such as Meta Stack Overflow, also have this issue.
Navigating to the actual post does show the correct information upon hovering over the equivalent tooltip
This post is community owned as of Aug 3, 2010 at 12:44. Votes do not generate reputation, and it can be edited by users with 100 rep