I've noticed that quite a many VOIP phones support PoE. While the idea seems great in principle (no worrying about power adapters anywhere), have you found it to be effective for enterprise-wide deployment?
My main concern is that all switches need to support PoE: so far as I can tell, plugging in a non-PoE switch in front of a PoE switch will mean that all devices under the non-PoE will not have power. Because PoE switches are quite a bit more expensive than non-PoE, and with PoE standards changing, this seems like it could be a dodgy investment.
That, and if you want users to take their VOIP phones on the road, then they'll need to remember to pick up an adapter or injector, and figure out how to hook it all together.
Is PoE better for point-to-point applications, such as running a WAP in some remote place that's not powered? Or, is it effective at the enterprise level?