[EGreg]

The correct place to dump users after they create an account is the Account screen, where they can fill out various sections, but don't have to. Each action on the site/app which requires certain info from the user (eg their location or interests) would have a link to an inline / popup allowing them to fill out that section before proceeding.

[vandingmils]

I could not disagree more.

I am never interested in building a social profile or entering preferences to some app I'm unfamiliar with. Like others comment, I'd like to get to using the product ASAP.

Signing up is already a hassle that should have been kept to a minimum.

[ci5er]

I may be an atypical and less social (more asocial?) than others. Or maybe I'm old and impatient. Or all the above.

Making me fill out, really anything, before I can drive the app around at all is a sure way to make me "nope" right out of there. Now, I understand that you said "don't have to", but a big screen of form(s) is an intimidating clue that you will want more from me than I suspect I am willing to give. I don't even know who you are yet.

Incrementally adding information during the use of the application to make operation/data/context more relevant or useful is fine. Not filling out a list of interests, for gods sake. And not 20 things, mind.

YMMV.