A Google Webmaster Help points out that Google handles most date formats in US format. So if a site has a date in the format of 04/06/2007, Google will read that as April 6, 2007, but in UK format, it might be known as June 4, 2007.

Here is a screen capture of one such result:

And here is the date on the actual page:

You can see more details on this at Google Webmaster Help, where Googler, JohnMu said he will pass this information on to the right people.

Forum discussion at Google Webmaster Help,.