Fixed, simply mistake on my part , whoops :)
onFetchItemList: function(inSender, inEvent){
var prof = this.userProfile;
var _gridList = this.$.gridList;
var shows = new enyo.Collection();
obj.getBrowse(prof,function onBrowseCallback(list){
ameba_lastListViewed = [];
ameba_lastListViewed = list;
shows = new enyo.Collection(list);
_gridList.set('collection',shows);
}