that would be one of the the feature in aaa, the accounting part. But lm not sure if you can narrow it specifically to routing table.
i have another idea , maybe just marking the routes in the routing table per destination basis by some extended acl ( and inject it in a route-map without any set command ,and integrate it to you interface) (just mark->match->count) then you can see how many packets have been matched and how many bytes they are by some basic show command..(eg.show route-map XYZ)
You can do some really cool things with netflow export and a good collector. This, however, does not tie it to a routing table entry, but you can filter down to destination subnets.