I've been wrestling with this for a while on 7.x-1.0+7-dev
When I run cron from Admin as my user, all scheduled posts get published normally. When run from crontab as anonymous, posts do not publish and this shows up in my logs:
action 02/25/2013 - 17:52 Saved Blog Post test Anonymous (not verified)
action 02/25/2013 - 17:52 Set Blog Post test to unpublished. Anonymous (not verified)
action 02/25/2013 - 17:52 Set Blog Post test to published. Anonymous (not verified)
scheduler 02/25/2013 - 17:52 blog_post: scheduled publishing of test. Anonymous (not verified) view
It looks like scheduler does it's thing, but there is an action setting the post back to unpublish and saving (even though I have not scheduled an unpublish action).
Any ideas / help would be greatly appreciated!