Earlier this year Twitter changed their sign-up process for new accounts. They ADDED an extra screen but boosted sign-ups by 29% through a process they call "gradual engagement".
There's a lot to learn from this for our own sites.
Gradual engagement is the process of moving a user through an application or service – actually engaging with it, and seeing it's benefits. With gradual engagement, new users are not just presented with a registration form and then dropped off a cliff (typical process in many Web applications).
Instead, registration is either postponed, or handled behind the scenes and the first time experience is focused on giving people an understanding of how they can use a service and why they should care to.
[lukew.com...] - with screen captures of before and after
Also of interest are the notes from a talk given by Twitter's chief architect Mark Trammell - at the WebApps Master Tour. Here are some early points he made, and the link at the end takes you to the entire outline:
Heavy users of Web application don't get that way over night. What kinds of things do they do over time that we should pay attention to?
When you watch people who are new to Web applications they are not clearly producers or consumers. Need to understand how people's use changes over time. Need to ensure people become good consumers first, then good producers second.