I was just looking at the messages part of this forum and noticed that there is no way to send a message to another user. Is this intentional, broken, or am I missing something?
I think you are missing something. Click on your icon in upper right. Click on the envelope. Then click on new message.
It is due to your user level. Brand new users are slightly limited to dissuade spammers, etc. It looks like you signed up about an hour or so ago, right? As you start viewing and participating in threads as a part of the community the forum software will automatically grant you a higher level which will also give you the ability to send private direct messages.