.co.in has been around a long time .in is the new boy on the block.
.in has proved reasonably successful with non indians with sales like Mails.in , Zoom.in etc
I have personally had a great deal of success particularly with the sale of .co.in names - well over 700 from just over reg fee to low/mid $x,xxx and still have a prime portfolio here TajMahal.co.in .
The other Indian extensions - net , org etc- unless they are very premium names I think currently they will have little value.
Good luck