I've just started using the NextGen Gallery plugin (thanks Alex) andhave noticed a very minor glitch with the sidebar widgets. If you specify a title for the widget it ends up being opened with the <H2> tag instead in the generated HTML rather than <H3> as used by other widgets. This can make things look a bit messy.
The problem is in widgets/widget.php on line 394; this currently reads:
$before_title .= '<h2 class="widgettitle entry-title">';
Changing this to:
$before_title .= '<h3 class="widgettitle entry-title">';
Fixes the problem.
Thanks again for the plugin. Apologies if this has been posted before.