Hi, how to achieve a WordPress.com-like comments in custom installation? Features it should have:
1) Built-in comments (no Disqus / IntenseDebate)
2) Comment form always visible (no "you must log in to comment" message)
3) There are 3 button below the comment form - WordPress login, Twitter and Facebook auth.
4) When "Users must be registered and logged in to comment" is selected, users actually have to log in using one of the three methods to be able to post a comment.
What mix of plugins / customizations will achieve this? There are social login plugins but I haven't seen any that would properly handle 2+3+4.