Oracle-sniffing is more reliable now, tracker-cache cleanup in certain intervals is triggered even when browser triggered archiving is turned off (for clustered environments - configuration changes might update tmp/cache/tracker of just one instance), $db->truncate() also resets a depending sequence's counter, table 'option' cannot have NOT NULL for option_value (if an empty string '' is to be inserted under certain circumstances), Piwik_Option clears that NOT-NULL-constraint just in case,  LogDataPurger.php got some debugging code, createTempTable() revised!