Ban it - there are several instances where derogatory comments were put against national icons, communities, social groups, indian culture and values and individuals. Also children can easily identify the sources of ponographic materials and download it.
Though there is a review mechanism put by orkut. com, it is not effective and time consuming. The status today is any one can write anything citing a reason of freedom of expressions.
If orkut can review the content before publishing it and remove the unwanted/deregatory materials, then only it needs to be given access in India