I agree that services should have their own infrastructure. If anyone's serious about making a service, they could program a webpage or hire someone to do it.
Regardless of my opinion in this particular subject, I completely agree with you in this statement. I used Bitcoin for many months before I decided to join this forum, I remember that I saw it as a... dirty? ugly? thing. And the thing that made me change my mind was that by not joining, I'd be unable to communicate with the people that run some of the trustworthy and honest projects in the Bitcoin community, and that use this forum as their main communication mean. Also, I thought that by joining I'd be able to get updates on interesting Bitcoin projects (and on the project itself) quicker and easier.
Unfortunately, later the "show unread posts" function returns results that aren't very insightful - and eventually scare away many newcomers. Among these results, there are lots and lots of gambling and betting threads. Is there a way to ignore specific threads or even whole subforums (permanently mark them as read)?
I don't think people should run their projects, "investments" and bets directly on this forum. I think they should be able to use it as a way to advertise and discuss their things, but the forum infrastructure shouldn't be used for just everything from "sign me up" to "cancel my account" and "here's my bet". There are betting websites for bets; projects should have their own independent infrastructure allowing for contacting the people responsible by the project (instead of relying on forum threads and PMs); and "investments", be them serious and honest or not, should have their own independent page clearly stating their rules and important announcements, instead of relying on bitcointalk threads with over 50 pages.
For me, "discussing" a project/bet/investment/game means either discussing an idea for e.g. an upcoming thing or discussing something that's established already. I wouldn't trust anyone who uses a mere forum post on a single website to announce a bet/investment/game.
In other words, that kind of things shouldn't live in the forum (homeless) but have its own "building" where people can enter.
About the "one forum for kiddies and another for adults" idea, it may seem very appealing at first, but I think that, unless you have some central authority who judges who is a kiddie and who is an adult (and then one may wonder: does it judge in a fair way, or not?), the end result would be that the kiddies forum would be empty, and everyone would show up on the adults forum (nobody would want to be called a kiddie).