I'm having the same issue.
If you read the SPAM Update on the landing page this is explained:
Due to a recent and significant increase in spam, all posts will now be moderated first. All legitimate posts will be approved and spam will be immediately deleted.
You may see one of two messages when you start a discussion. The first message may say that your discussion has been sent to moderation. Which will will moderate as quickly as possible.
Another, less friendly, message may say: "Access to this place or content is restricted. If you think this is a mistake, please contact your administrator or the person who directed you here." In both cases, your post will go to moderation. We are planning to upgrade our platform this week and hopefully we can eliminate the more offensive message in the process.