I think it was utterly, totally, completely awesome.
I love how they didn't mess around in the slightest. From the very first frame, they were not cagey in any way, they simply showed us exactly what was going on in the tunnel and who was down there.
I was expecting continued secrecy about the tunnel. Instead, we clearly saw a person, with a computerized control room (albeit with 1970's era technology, which actually makes sense come to think of it). A whole BUNCH of pent-up questions were answered in an instant. Certainly not every question was answered, but those scenes sure knocked down a whole bunch of them.
The hard part is, of course, now that all those questions are answered, there's a whole new set of follow up questions.
Brilliant, brilliant show.