After trying many times to install new yahoo go! 3.o on my E71 and fail . I try to remove first my memory card before instalation process. And it works well. I think there is a bug (my firmware is 100.07.76, you can check your firmware press *#0000# on your phone) when we want to install some application on E71. We can download it at: http://www.get.go.yahoo.com/ .
We can add new widgets to our phone. See Map, yahoo messenger, better news with this new Yahoo Go.