E-Gold got used by customers even sketchier than anything I've seen BTC used for -- I used to think of it as the carder currency, but it was also heavily used in the CP world, I think. They really hated e-gold, but chose to use the MSB laws against it.
I know the e-gold guys tried to go out of their way to be as compliant as possible, too. They were fundamentally pro-liberty/pro-gold people, not involved in the "sketchy" business, and had been fully cooperating with authorities as much as they could (e-gold was not really about anonymity as much as "honest money"; they had bank-level KYC requirements for accounts at some point, although initially they had none.).
The interesting question is whether fully KYC/etc. compliant Bitcoin businesses will be allowed to register as MSBs, or if there will be artificial roadblocks put up. One issue is the global pseudonymous network that is Bitcoin once it leaves a KYC-compliant site, but that isn't too different from either a KYC-compliant bank that pays out physical cash or one which sends SWIFT wires to overseas banks with more lax KYC requirements (or issues prepaid debit cards).