Here's the problem with saying that a.) retailers as barrier to entry - I don't buy retailers alone as a barrier, given retailers are likely to only do one or two promotions at great cost to themselves, other articles have talked about this issue.

b.) Mindshare as barrier to entry -- I don't buy the mindshare argument when the a strength, as noted in the article is the urgency, the deal (the store is the brand that matters -- probably as much as the conduit if not more). Beyond that, mindshare is primiarly money invested into viral loop on facebook/myspace and brand ads.

c.) Infrastructure? Um, it's just lead generation -- I see the larger infrastructure as outward bound direct sales to merchants. (sites like leapfish.com have sustainable conversion rates on outward bound telephone sales to merchants -- online are they important ? well...)

There are already huge investors knocking off the idea, and as for the cash issue, the article talks about the "negative working capital" needed.