There is something wrong with Dark Tranquillity's page; in every space where the release date of an album would normally be shown, all I see is this:

Warning : mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/morrigan/public_html/login.php on line 83

Of the bands I've checked, I only see this error on DT's page.

edit:
Similar lines appear at the top of the page, both above and below the band logo, and near the bottom of the page, directly below the "Links" tab. There doesn't seem to be a problem with the reviews or individual album pages though.

I don't see it. I'm too tired to try to find out the problem, but one quick question - could it be your browser?

I swear a similar question was brought up not so long ago.

Maybe it's my browser, though I tried it on IE and Firefox. But now the problem is apparently gone, so there's no issue anymore.

That error has to do with the site's code/server issues. It always goes away by itself fairly quickly.