Object identifiers are used in a variety of content distribution arrangements, including—but not limited to—peer to peer networks. The object identifiers may be of different forms, including digital watermarks, fingerprint identifiers, etc. Through use of such identifiers, sometimes in conjunction with related databases, a number of functions and services can be readily implemented. These include governing content uploading/downloading in order to inhibit piracy, and to enable subscription models. A variety of other features and arrangements are also detailed.