Laurence, and a lot of other people at Commentary are upset about the "renaming" of Pretoria.
The city centre will retain its name, so the name "Pretoria" will not vanish entirely. The City of Tshwane has been in existence for around 5 years, so registering it as a place name is not a big issue. In fact, apart from the name being registered, it appears that little else will change.
What will be interesting is whether the area that comprises the entire municipality is registered as "Tshwane", or just the old city of Pretoria, which is a part of Tshwane. Registering just the old Pretoria as Tshwane will probably cause confusion in places like Centurion, which were not part of Pretoria, but are part of Tshwane.
I also was taken aback when I read this report that the name change may cost 1.5 billion Rand.
I grew up in a rather underdeveloped part of what is now Tshwane, and despite the promises of the municipality, the infrastructure remains in a poor state, and it is economically underdeveloped. 1.5 billion Rand would be a nice sum to kickstart development, instead of being wasted on a symbolic and meaningless gesture.
By the way - it seems politically foolish for the ANC to give the opposition a hot-button issue with which to mobilize support.