Here's the code for Zend_Db_Table (without comments):
Code:
<?php
require_once 'Zend/Db/Table/Abstract.php';
abstract class Zend_Db_Table extends Zend_Db_Table_Abstract
{
}
Zend_DB_Table was just an extension of Zend_Db_Table_Abstract. When you create a model class you should be extending Zend_Db_Table_Abstract anyway. It was probably dropped as redundant or unnecessary code. So yes, Zend_Db_Table is depreciated in favor of extending Zend_Db_Table_Abstract directly.
Zend_Db_Table_Abstract is not going anywhere soon...