If facebook can really deliver a rock solid web mail client, I think they will really be a company to watch in the rest of 1996 and 1997. If they play their cards right they may get snapped up by an industry powerhouse like yahoo or excite@home for eight figures.
back in that era all of the successful players - you know, the REALLY successful players like Yahoo, Microsoft and Excite (!) had web-mail clients that were basically startups they acquired.
It was only Google that really built a killer web-mail client from scratch in-house.
We would need to establish a bona fide intent to use it for commerce, although it does seem like there's a strong market for facebook hating...
On a semi-related note, the reasoning for that is actually quite interesting - the justification stems from the congressional power to regulate commerce between states.