metal450 said:

As of 1.0.0-rc9.9227.b:

-next_post_link() does not show the next post if it's private, even if the currently logged-in user should be able to see it.  This worked properly in 1.0.0-rc9.9216.

I'm having trouble reproducing this one for a logged user. Tried both without teaser and with teaser, no hiding private.

Does this have something to do with attachments?

metal450 said:

The next/previous  links bug is for regular posts, when logged in as myself (administrator, who should see all posts).

Ahh… there's the important condition. For my debugging purposes, "for the currently logged-in user" is entirely different from "for the administrator".

This was a casualty of recent performance enhancements to reduce memory usage when logged in as administrator. Fix coming soon.

Now I get this when not logged in:

WordPress database error: [You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '( ( ( ( ( ( 1=1 AND wp_posts.ID NOT IN ('18', '30', '33', '36', '41', '43'' at line 1]
SELECT DISTINCT YEAR(post_date) AS `year`, MONTH(post_date) AS `month`, count(ID) as posts FROM wp_posts LEFT JOIN wp_term_relationships AS tr ON wp_posts.ID = tr.object_id WHERE 1=1 AND wp_posts.post_date > 0 AND post_type = 'post' AND wp_posts.( ( ( ( ( ( 1=1 AND wp_posts.ID NOT IN ('18', '30', '33', '36', '41', '43', '47', '50', '56', '61', '66', '76', '101', '102', '117', '124', '127', '128', '148', '149', '217', '226', '228', '229', '232', '234', '249', '253', '259', '263', '266', '267', '270', '277', '279', '286', '299', '302', '305', '308', '310', '311', '320', '329', '333', '335', '338', '349', '356', '359', '362', '364', '371', '373', '377', '381', '390', '397', '408', '409', '410', '414', '424', '452', '456', '484', '951', '1018', '1240', '1285', '1384', '1427', '1445', '1479', '1545', '1581', '1607', '1678', '1684', '1697', '1699', '1732', '1788', '1832', '1884', '1899', '1932', '2171', '2181', '2239', '2442', '2567', '2716', '2844', '2910', '2958', '2982', '3045', '3082', '3398') ) ) ) ) ) ) AND post_status = 'publish' GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date DESC

Looks good!