>Using an existing system bypasses a huge part of that.
Not really. I'm not sure it's any less work to move an entire app to use a new interface than to move to a new file store. Your mail app doesn't implement an HTTP interface that a unified search engine could consume.
Not really. I'm not sure it's any less work to move an entire app to use a new interface than to move to a new file store. Your mail app doesn't implement an HTTP interface that a unified search engine could consume.