The celebrities in this case, are using twitter as an ADVERTISING platform. you said it yourself- would-be celebrities are trying to use twitter to "get the word out". is this now not an opportunity worth paying for? Would the fans, noticing they are unable to follow Ashton, blame twitter, for charging a reasonable price for that huge megaphone, or Ashton, for being unwilling to pay for this enormously powerful broadcast medium? I don't think, in this case, limiting growth is a serious issue.
> for the same reason as above, you can't. A lot of people come on facebook and stay there because of apps, charging devs for API access will kill innovation. Also, if something is popular and growing, taxing it will be bad for both the users and the dev if the dev can't pay. Also keep in mind that most popular apps may not have a monetization strategy yet.
Apple charges $99 for an SDK. straight up flat fee, annual charge. Are you saying this has seriously harmed innovation for iOS?
What I'm proposing isn't even that. It's charging for say, having an app that has more than 10,000 simultaneous users. If you are charging money for this app (and many twitter clients do), is asking for a fee really as harmful as you claim? I don't think so.