I think orkut is good..but more MB eater is you are using limited MB net..
Yahoo 360 is also same.. but yahoo messenger is quite faster and better..
now orkut has upgrade some services and make it better..
i think orkut is better than yahoo bcz in orkut there are millions of people from different countries. you can talk, put on videos, and u can join different types of communities. i myself have found websites of free games and software from orkut
Both are good at different ways. Orkut is good in finding old friends,classmates.. thats emotional.. where in yahoo is having many features, which can not be given in other tools. So both are good in their own rights