I suggest you generate in the data string
<td class="format-this">1000.00</td>
then in jquery,
var MyDataToFormat = $("<div></div>").html(data);
OR
var MyDataToFormat = $("<div />", { html: data }) //thankz for suggesting this
now you will get a DOM object.
then use number formatter Jquery number formatter like this one to format those classes.
$(MyDataToFormat).find('.format-this').each(function() {
$(this).html($.number($(MyDataToFormat).children('.format-this').html()));
});
This will change the html inside the DOM with ure format.
Let me know if this help, haven't test, wrote it raw
sample working, http://jsfiddle.net/q46LC/