Sometimes I want to keep my privates, private, other times, not so much.
Will coderwall let people know about contributions I've made to private repos? Most of the contributions I'm OK with being known, but not all.
In the future, maybe.
Until then, no, achieving badges based on private repos will not earn you the related badge.
think it's neat that u stream that thru but if u work primarily on private repos like me, there are no badges to show. - @timfernihough, 31 January 2013
we're looking into add'l badges in the future too - @coderwall, 31 January 2013
Since those comments were made last year, if you're not seeing any badges related to activity on private repos, it's still not implemented.