之前的建议方法是把在xxx.info.plist文件里把
icon already includes gloss and bevel effects 设置YES
在Xcode5下，重复实现不成功，今天最终找到解决方式，假设使用xcassets设置方法，须要选择iOS icon is pre-rendered 的选择框，如图
xcod5在iOS5下白图标问题，
http://iphonedevsdk.com/forum/iphone-sdk-development/115604-ipad-icon-appearing-white-on-ios-5-using-xcode-5-0.html
http://stackoverflow.com/questions/19220082/support-of-ios-5-0-icons-with-xcode-5