re:Small Exchanges

This brings up an interesting question. I have several BPX ATM switches
that I am not using for anything, and I had the bright idea that I would
start up some AADS-like exchanges around the country if I could get enough
interest. I pinged some of the Dallas area ISP's about the possibility of
connecting (I still know some of the guys around here that haven't been
gobbled up) and while some expressed interest in connecting, it didn't seem
like enough of them were interested to warrant the effort. With the
expansion of PAIX and Equinix (and others) into some of the other major
markets, will metro exchanges become a thing of the past? Are there simply
not enough medium-sized ISP's left in middle-tier markets to justify these
types of exchanges? And are the bigger ISP's simply not interested in
connecting to any of these metro exchanges?

An even better question to this community is this:

If I built it would you come? What markets would I need to locate these
switches in to make it interesting? If I were to offer connection at cost
+10-15% (for O+M) would that make it more interesting?

By the way -- the ATM switches seem ideal for this to keep costs down (no
collocation necessary), even though the marketplace seems to be moving to
Ethernet exchanges. Does anyone have issues with ATM (other than the
cell-tax) for this application?