I think the future may well be lots of blockchains talking to each other via something like Polkadot (http://polkadot.io http://polkadot.io). There may also be

I think the future may well be lots of blockchains talking to each other via something like Polkadot (http://polkadot.io http://polkadot.io). There may also be use cases for private blockchains, and there are startups pursuing those, such as http://chain.com http://chain.com (though I'm not sure why regular databases wouldn't work for most of those use cases), but I think there is also a need for a global decentralised network (or networks) for other use cases - global transactions/contracts, decentralised companies, probably other use cases yet to emerge. Current scaling/latency issues with blockchains - there is ongoing work to solve those via off-chain networks, sharding etc - it's still early days, it will take some time to develop.