How does Twitter make money?

Hmm, ok. Seems like only a very small portion of their userbase actually makes use of text messaging for tweets. I guess it would be enough for a small revenue. Is that really the only revenue stream?

Twitter doesn't charge its users for the service (at least for now). It's our mobile phone companies who are making the money from our SMS usage.

In fact, Twitter pays the mobile phone companies to send us our notifications.

See also this page on Twitter's knowledgebase for more confirmation.

Ok, so that revenue source is out of the picture - which begs the question of how they continue to operate? Where is the revenue stream that I'm obviously missing here?

For a discussion on how Twitter will make money, it might help to read this blog post from Fred Wilson about Twitter's business model. Fred's VC firm invested in Twitter.

Ah, ok. So the real answer is they don't make money...yet. Thanks. At least it wasn't that I couldn't identify a revenue stream but rather that there isn't one at the moment. :)

So, I wonder which direction they are likely to take when they do decide on a business model: Ads? Subscriptions? Both? (Or likely, ads on free accounts and none on subscription accounts?)

Anyone have any thoughts on something else entirely?

Actually, if I remember right, they had a few Google ads for a little while (on individual tweet pages), but I doubt that brings in any revenue (not many people view INDIVIDUAL tweet pages, I'd think). It seems like those ads have disappeared.