[jQuery] dealing with a post (json) callback

[sneaks]

hi, in firebug my callback data(object) is like so:

[{"product_brand":"Creative Recreation","product_name":"Cesario
Hi","product_slug":"CRM-CESAR-PRIME-
HI","product_active":"1","product_description":"mens- red"}]


i have never noticed the square brackets before ...
but when i attempt to use each to oterate through the obnject for
values... i get nothing:

var obj=eval('(' + json + ')');
console.log( obj );
jQuery.each(obj, function(i, val) {
  if (i) {
      alert(val);
      jQuery('#'+i).append(val);
  }
});


this has always worked fro me before and i am not doing anything
different this time... but i would appreciate any insight into what
may be happeneing here