I’m not sure I’m as optimistic as you are that the FCC will adapt to the internet, as opposed to it trying to impose requirements from the circuit-switched world to the internet. Note that Skype could (with a bunch of work) implement CALEA by always routing through supernodes (which could act as interception points - though fully avoiding it being sniffed is tough without making all supernodes under Skype control). Right now I think Skype will (when possible) send directly.

I disagree with one of your statements: I believe CALEA may apply to enterprise VoIP.

The reason is that the same argument used by the FCC to ensnare educational institutions (”because they touch a public network”) would apply to enterprises. In fact, the CALEA ruling would seem to imply that a corporate (”private”) network that touches the internet would be covered by the same CALEA rules that apply to ISPs.