Welcome to Lightroom Forums.
Can you outline the salient differences between your plugin and Jeffrey Friedl's, which I'd expect the majority of us are already using?
1. Each photo is uniquely identified in Flickr. Regardless how many Photosets (LR Collection) you put them in the will be only one of it on Flickr.
2. Masters and Virtual Copies are uniquely identified. After you published a photo and decided to have it alternatively post processed you can make virtual copy and both will have a unique instance on Flickr.
3. If you try to republish a photo a few times either because they appear in different Collections or by mistake, my plugin will check the status of the photo when it was last edited and compare it to when it was last published.. if recently edited it will republish if not it will skipped it.
4. Collection is reflected one to one on Flickr. If you have have a collection then you will have Flickr Photoset of the same name. If you change the name both will be sync.
5. I am aiming at simplicity, Jeffrey's give you more control.
6. My plugin is new. It will get better over time, I hope, with your inputs.
I was a user as well of Jeffrey's plugin. But started to develop my own then Lightroom 3 started to get into the picture. Export with Jeffreys's is great but publish is not really something that I am happy with.