In the beginning, dates next to content on the internet were ugly things. We used to see date/time strings like 07-29-2010 16:31 and that would be it.
Then, options were added to allow administrators to specify a date/time format, and you could see output such as 4:31pm, Thursday June 29th 2010.
Later still, it was possible to output times relative to the present, so one could see dates like 3 minutes ago or Yesterday at 6:15pm.
However, these relative dates can be nasty when it comes to anything that is going to cache the page output. If a search engine slurps up the page, its cache is going to forever be wrong, as it will be locked at 3 minutes ago even when the content is weeks old. This can also be a problem for long threads. By...