You'd be amazed at just how little of that knowledge really became obsolete. A lot of the features I'm introducing were ones I used in the BBS days and though the screen names are different as are the individuals behind those names, collectively we're exactly the same people, with the same requirements from this kind of site.
We're also identical as "a market". We'll fork over money only to sites with the feel of "permanence" and "community" and that give us things we want in return for our money.
Sure, most of the technical aspects (aside from database structures necessary for messaging) became obsolete, but hardly any of the non-technical things have.
Market Data 
Markets 
AI
