Well, .co.in is not the main ccTLD for India (.in is) so it isn't worth as much. However, they are nice and short, I'm sure you will find a buyer eventually.
Thanks JYM. I'm still trying to work this one out:
co.in seems more popular for live sites
co.in has had larger reported sales
co.in has been around longer
.in has more interest and more bids from resellers
.in is shorter and a better domain
The jury still seems to be out about India's main CCTLD.