Increasing prices, obviously, can help your bottom line - as long as you don't alienate you users in the process by increasing them too much. But what if you're running a fremium model, free accounts for users hoping that the features of a paid for account are inticing enough that they'll give you money, and it becomes too expensive to service them. Can you get away with moving to a paid only model>
The move from 0 to even 0.01 is an infinite jump especially in the eyes of your users, if for no other reason than you're asking them to do something else; put in credit card details. So I think It's going to be interesting to watch Zoto who are moving from a fremium model to one with only paid accounts [via mashable]
I think they'll probably suffer short term, certainly in visitor numbers, but that does it really matter long term as long as they're acquiring paying customers? Even if the number they're acquiring on a monthly basis drops off those users aren't paying the costs of the freeloaders, so Zoto may actually be better off with lower levels.
Anyway, if I remember I'll probably check back and see how things go in a few months.