Amazon Prime is adding streaming music to its subscription service, while Pocket just launched a premium subscription service.Five music industry sources have confirmed that Amazon plans to add a streaming music subscription by July of this year, reported GeekWire. The service would provide Amazon Prime Subscribers with music six months after release, which seems like a bit of a delay (and counter to subscription marketing best practices that state that consumer media sells best when subscribers get advanced access). But Amazon also sells digital downloads of music, and since the streaming music service looks like an added subscriber benefit, not a separate subscription plan, the six month delay may be in Amazon’s best bottom-line interests.Meanwhile, Pocket (formerly Read-It-Later) launched a premium subscription service this past week. For $4.99 a month or $49 a year, subscribers can get a “permanent library” of the web sites and articles they clip and save through Pocket. Subscribers also get enhanced search capabilities.In all honestly, Pocket’s model seems like to have a weak value proposition to customers. The service already more-or-less stores all your articles permanently, so it’s not clear how appealing the “permanent library” will be in itself. And enhanced search capabilities are nice, but I’ve never heard of anyone paying money for them.It’s also true that there’s some amount of subscription fatigue going on for consumers, and more bundled options like Amazon’s will be more viable in the long-term.What do you think about these two new subscription services? Would you subscribe to either?