Yep. And to make matters worse, a VoIP network is not capable of delivering the same services that a TDM network can.
Devices using sensitive timing of dtmf signals such as fire alarms and other communication devices, as well as devices such as fax machines and modems do not operate well over VoIP networks.
There are a tons of devices like these out there and if they cannot operate reliably over a VoIP based network then they will either have to be replaced or migrated to either cellular or IP based communication methods.
VoIP is great for voice, but voice isn't the only thing that the telephone system is being used for. The industries that are relying on the "quality" of a TDM based telephone phone will soon have a lot of upgrading to do.