@Anonymous Coward - I didn't write the post. I linked to who did though. I see you've already copied and pasted your comment to the original post.

We'll have to see what comes out of that discussion regarding Akistmet and the guideline about requiring registration to use the plugin.

From what I've been told, it's perfectly ok to upsell to an upgrade or paid support but a lot of it has to do with how it's worded. This is done on a case-by-case basis.

#3 was addressed by Mark in the comments, hope you can give his answer a read.

I'm not sure what his list of guidelines highlighting what not to do has anything to do with crappy plugins on the repository.

Nice name by the way :)