Their email to users offers a transition to the Small Business product... which appears to be the same product at $10/month/device. So this is really a pricing change, though you can enjoy a 75% discount for a year while you decide what's next.
Be careful if you rely on old versions and deleted files being backed up indefinitely. Their Home offering includes this, but it looks like Small Business does not.
edit: I got confused - Small Business likely still offers indefinite retention.
