what advantages would a WiFi camera provide over a 5.8 GHz camera?
The WiFi standard has built in channel negotiation, client "rules", and quality of service. You can have as many cameras connected to an AP as the AP will support, and they wont interfere with eachother or other WiFi clients. A 2.4ghz or 5.8ghz wireless camera would interfere with 2.4ghz and 5.8ghz WiFi devices.
Also, 5.8ghz has poor penetration, its going to have trouble if there is anything between the client and the AP. 2.4ghz is better if the channels are clear of other devices.