ZydoSEO - 9:15 pm on Jan 8, 2013 (gmt 0)
As piatkow eluded to... reciprocal linking is not necessarily bad so long as each site ads value to or benefits the other sites' users. But I would be careful of doing too much reciprocal linking.
In some verticals it's the standard way for sites to interlink... specifically in very niche verticals like certain hobbist sites... because there are so few sites related to that vertical. But generally speaking, this should make up a very small percentage of your backlink profile.