I know this is slightly OMNI, but I stopped trying to do business down there because several great projects went in the red because various intermediaries (including the government) sucked up all of the profits.

That having been said, the common lounge concept makes some sense to me. Think about airlines that only have one flight per day like CX to Boston. It's cool that Delta lets them use their lounge, but perhaps they could get a better deal from airport authority if it was the landlord.

We also need to take into account for the fact that many airline lounges get very low usage. A few restaurants might be a better use of space than a mostly vacant lounge. (Unfortunately, I think we'd just end up with more useless luxury retail.)