What patio11 is saying is that Dwolla underestimated the scam potential by accepting payments with are rechargeable and giving non-rechargeable "digital cash" in return.

Basics of the scam: Deposit in Dwolla, buy Bitcoins on an exchange, send bitcoins to your own wallet, chargeback Dwolla deposit.

A couple of months ago TradeHill, the second largest bitcoin exchange, discovered Dwolla billed them $30K in chargebacks despite their claims of never doing that.

It's this Dwolla issue that stopped the influx of new money into Bitcoin and now the price is 90% down.

This is a key problem for growing any kind of digital cash like economy: somebody needs to take the risk of turning chargeback-money (USD) into cash-like money (bitcoin), or you need to have a network to somehow take physical cash.