I would (in theory), love a unikernel for the work I do. Our bare metal boxes run about 20 Unix processes -- cron, syslog, sshd, etc plus one server daemon. It's nice to have a familiar environment, but we could run on fewer boxes without a general purpose kernel and general purpose memory protection that we don't strictly need, especially for nodes that could easily be tweaked to forgo local disk access (because filesystems are tricky, I'd rather leave nonephemeral storage with something proven)

That said, we're not moving in the direction of unikernels, but it has a clear application in my mind. It's a fair bit of work to migrate, and I've yet to see a practical comparison, so it's unclear what the actual benefits over conceptual benefits would be.