We use a variety of WAN providers and many deliver us gig-e services.
No provider appears to deliver the same service the same way. Some circuits are "clear" meaning as far as our endpoints know, the only thing attached to them is our own equipment on the other end. In these instances, for example, if we unplug either end, the other end sees a loss of link.
On other circuits, they aren't clear, even CDP neighbor shows us the local handoff devices, and ONS or whatever it happens to be.
We usually opt to set up all our gig wan circuits as .1q trunks just in case and use SVI's. A handy trick on new turnups to identify if the end to end is really established is to check STP for the vlan of the link. Only one end can be root. If both ends think they are root, you know you don't have a good L2 connection.
And if you can't get the circuit live and the carrier isn't handy, a quick command to try on your interfaces are
which turns off DTP, and DTP is teh suck, so turn it off anyways
which shuts off speed/duplex negotiation. this is a clause 37 thing if you care. Different carriers handle it differently on different gear. These two things can help.