I've been having "non posting" issues with 1.4.4 so I downgraded back to 1.4.3 some time ago.
I posted to my blog this morning using 1.4.3 and the post appeared on the blog.
I then upgraded to 1.4.5 hoping that the issues I had with the earlier version would have been fixed.
Once the plugin was installed, I emailed another post to the blog and then used the "Run Postie" button to determine if it would work successfully.
Sadly I was greeted with "1 message deleted" (or similar) text on the screen so It's definitely not working for me. - So it's back to 1.4.3!
I'm not really savvy with this sort of stuff, so really simple, step-by-step instructions on how to debug/fix the issue would be greatly appreciated.