I'm a very satisfied user of MarsEdit, I love it, it makes my day to day posting quite easy and automated. Now, I'm new to the Mac, so please forgive my naivete if what I'd like to see added to MarsEdit already exists and I just haven't discovered it yet.
I worked on a Windows product called Visio for 10-years. Visio was completely scriptable via OLE-Automation. One of the coolest things about the model was the ability to hookup code that could be notified when an event took place; like the position of a shape changing for instance. Very cool, and very handy to third party developers that wanted to create their own custom solutions on top of Visio.
Now, I don't want to create a custom application on top of MarsEdit, but I'd like to write some scripts to help automate some things I'd like to do with each and every new post. I'd like to be notified when I publish, period. If that notification could include some data that told me if it was a new post or a republished post that would be extremely cool, along with the post URL and maybe a few other data points, not sure what those would be right now. :-)
I'd like to receive the "PostPost", or "PostPublish", event so I could generate a small URL using TinyURL, and publish the resulting URL to Twitter in a standard format, something like...
Weblog Post, Title: TinyURL
That's it! I'd imagine MarsEdit is most of the way there, I know you can script it with AppleScript, maybe I just need some lessons?