Pro or top-tier accounts have been around for years, long before the current crisis. LinkedIn and Linden Lab both have claimed to be cash-flow positive (I believe last year or earlier) because of upgraded account services that come with special features, and I know Ning and a few others have business plans based on fee-based extras.
how economical is it to be making $5 credit charges for several thousand users ever month? I would think that visa/mc would eat your revenue for lunch there. Is there anyone out there aggregating these sites' little charges for them?
The typical cut taken from a $5 transaction would probably look like about 30 cents flat fee plus 3% = 15 cents with another maybe 5 cents per transaction (on average) from the flat fees you pay to all of the people helping you process cards if you have particularly low volume. That's 10% lost to processing, which clearly sucks, but you're still taking home $4.50...
Its not that bad. On a $5 charge, you'll lose like 50 cents in credit card fees. Sure when you multiply it by the 2-3000 users, you end up losing a few thousand bucks...but hey cost of doing business.