What is Posterous' business model?

I've started using Posterous a few days ago for my personal blog and was wondering what was their plan to monetize their service. They don't advertise on their hosted blogs and do not offer a premium, paid service.

Does anyone have an idea ? Maybe they're waiting to get bigger before moving to a freemium model ? I'm just asking out of curiosity... if anyone has a guess, go ahead !

PS: Feel free to tag this appropriately !

evolving as they go.

from their faq:

Yes, Posterous is enthusiastically a
free service. Later, we'll be adding
premium features we know you'll love,
but there will always be a useful free
version you can use.

more themes and widgets perhaps. One could take a stroll through the Y combinator / hacker news threads and get better insight.

I know Sachin Agarwal, CEO of Posterous, and he seems to have a solid idea of the way micro-blogging should be. SIMPLE. The Auto-Posting is what really sets them apart, and being able to blog via email.. good stuff, but they also allow you to override the CSS, and it's super simple. Their focus seems to be on the software more than just making some small change via ads.

He worked @ apple for many years, and has never owned a windows machine. not sure if this is helpful, but wanted to give my two cents.. build my rep here. :)

Paul Graham, from Y Combinator, has a big focus on making something people want and then figuring out how to monetise it later. His rationale is that it is much harder to make something people want than to work out a revenue model. He reckons that's what the VCs are for!!