The idea that they want to keep growing as fast as possible, and they don't want to retard growth by monetizing makes a lot of sense to me. It especially makes sense because people are using the product in ways that the Twitter guys never even imagined. They don't even have to figure out new ways to use Twitter, their users are doing the creative stuff for them, they just have to pay attention. But if you monetize in the wrong way, it can have the unintended consequence of preventing some awesome-currently-unimagined use of Twitter. And that is much worse than a change to an abstract growth curve.
The other thing I wonder about is if their monetization strategy involves some technical challenge. Remember, their product is relatively straightforward from a technical standpoint, not to trivialize what they've done at all, just to make the point that they have gotten here in a short period of time with a very small number of guys. What if their preferred method of monetization involves solving some technical problem that they just haven't resolved yet?
The other thing I wonder about is if their monetization strategy involves some technical challenge. Remember, their product is relatively straightforward from a technical standpoint, not to trivialize what they've done at all, just to make the point that they have gotten here in a short period of time with a very small number of guys. What if their preferred method of monetization involves solving some technical problem that they just haven't resolved yet?