I've been hearing more folks talking lately about Bitcoin's use more as the "reserve" cryptocurrency and mainly thought to serve as a store of value/wealth. Other cryptocurrencies like DASH/PIVX/etc with their fast block times could likely be used for your typical micro-transactions and merchandizing applications.

And Monero for applications where privacy/security is of utmost concern.

Ethereum as a "platform" to host/support all types of crypto-related applications (i.e. DAPPs) and customized blockchain/smart-contract endeavors.

And who knows, subsequent to the success of the Steemit decentralized social-media platform, what other goodies are forthcoming on the STEEM blockchain?