结果这段代码在firefox中生效，在opera中也生效，但是在Safari和chrome中却没有效果，于是我上jQuery的官方论坛，和StackFlowover
论坛提问，后者有人回复我：
　　I assure you I was using $.ajax with Chrome just five hours ago at the office, and had no such problem.
　　I also imagine they use it here on SO and I have no problems here. I have no problems on jQueryUI in Chrome. I think it is your code.
大意就是斩钉截铁的说他用起来没有问题，是我自己的问题，我也纳闷了，后面也有人给我的建议更复杂：

You should use chrome's or safari's built-in developer tools (ctrl+shift+i) to track JS errors and track actual AJAX requests.

Is your code wrapped in document.ready? Is there any erros in javascript console? Also try to output something after success callback line.
Another cause for this could be incorrect mime-type for your XML file returned by server. It should be [Content-type: text/xml].
You can check that in chrome's or safari's built-in developer tools - just look for headers tab when xml resource is selected.
If it 's actual problem, you may need to tweak web-server configuration (main config or .htaccess for apache) to return correct mime-type

毕竟是自学jquery ajax框架刚起步……就遇到这么棘手的问题，的确麻烦……

但是，由于我一个不经意的发现，问题迎刃而解……

我用firebug查看成功后的页面元素状态，发现：
代码如下:

cocept


我恍然大悟，原来这种直接用pretendTo插入的方法会连tagname也插入进去，难怪chrome和Safari不能识别（从另一个方面来说Firefox原来强大这么多……）　　于是修改后的代码如下：
代码如下:
success: function (xml) {
$("#contain").html($(xml).find("app[id='id-1']").find("auther").text());
}

先取出所需元素的text()的值，再以修改html的方法html()插入容器中，大功告成啦！测试均通过