There is really not much privacy. All details you upload will be published to anyone browsing this website. We however, do well to shield you from spammers and crawlers who in the end will spam.
Ok! Put in a much better perspective, this website is an open community of practice - the developer community. This community is made up of users who very much understand the importance of networking (both social and non-social) and thus already have almost all of their profiles in the public domain on one website of some sort. This website just spins off of those public profiles as well as the voluntary decision of users who wish to get listed.
All data is public and cannot be deleted once uploaded but can be edited. Editing is restricted to only the email attached to the listing. Developers can post details of their fellow developers but again wont be able to edit the details if they used the friends' email when uploading the listing.