EDIT: 2 hours later...
Alright, this is crazy. Somehow, the Twitter post came through now, but it looks all screwy.
Even worse problem now, though, and yes I did install the new update you just released to see if that would fixit . Somehow, I can't access my home page now. Every other page loads, but not the home page.
Since I have been working with your plugin for a few hours now, that seemed the most likely culprit, so I went to my server and changed the name of the plugin to disable it. Now the home page loads. Change name back, and it stops loading again. Deactivate plugin, and my home page loads normally. Re-activate it, and it gets the 500 server error again.
This plugin has been working great for me until the updates started a few weeks ago, and immediately I started having posting problems that I had to work out. Now I'm completely lost. :D