Not sure about this.. I have seen it, couldn't duplicate on my site, and not sure why this site was getting it.
Warning: explode() expects parameter 2 to be string, array given in /admin/applications_addon/ips/blog/sources/classes/post/blogRssImport.php on line 291
if ( !is_array($data['rss_cats']) )
{
$data['rss_cats'] = explode( ",", $data['rss_cats'] );
}