Q: iMessage will not send messages, iMessage will not send messages

Yes there is. Go to settings > messages > show subject field > off. Hope this helps.

That is precisely my problem. My iMessage will work when I'm connected to a good high speed network but when I connect to mine. Messages take forever to send. I have found that the closer you are to the router will change this time.

I was having this problem as well, but it just started last week, even though I updated to Mavericks when it came out.

I tried everything suggested in this and similar threads - resetting the keychain, repairing permissions, clearing the NVRAM, deleting every FaceTime and Messages plist file, checking the date and time, and finally reinstalling Mavericks. None of these things worked, so I made an appointment at the Apple Store. The Genius went through many of these same steps and after conferring with three of his coworkers and spending forty-five minutes working on this, he fixed it.

You know what he did? He turned of the firewall, restarted the computer, and turned the firewall back on with no changes to the settings whatsoever. Now it works. Maddening, but I'm glad these programs work again.

Thanks Nicksageek.  I followed your steps and it worked great.  I recieved notices that my phone had been added back to my iMessage account which confirmed the previous failure to connect.  Now it is working perfectly and sharing messages to my iPad and keeping accurate delivery notices.

Cheers!