No, they haven't.<p>These subnets have not been <i>advertised</i>.<p>The difference is that when a device tries to send a packet to 1.1.1.1, your PC would send the packet to its default gateway, that gateway would send it to your ISP, and one of the ISP's edge routers would determine that there was no route to the host and reply with a message stating the packet is unroutable.<p>For the classic RFC reserved subnets, like 192.168.0.0, most routers were setup to drop any inbound/outbound packets addressed to or from those subnets, which is more like routing them to /dev/null.