I just developed a Wordpress plugin, which is now listed on Wordpress.org. I put the donate link to my personal site. I have a few questions: 1. Could this have any effect on my ranking? 2. Do people ever click the donate links? Although I like helping people, I would just like to know.
People do donate, but it's a tiny percentage. The amount varies, but if you have a 0.1% donate rate, that means you would need 1,000 downloads before seeing the first amount of money. The only real way to make any type of money with this is to make it a regular job, as in you make a lot of plugins, become well known, and people start looking for your plugins.
It won't affect your plugins' ratings. If you are going to list it for free anyway, you might as well include a donate link. It doesn't hurt. But don't just include it on your personal site; you can also include it on the options page for the plugin that people view within their Wordpress control panel. I've seen a number of plugins that have a donate link and Twitter link included on the options page itself within the control panel, and it would definitely increase the number of views it gets.
Go for it. I use WordPress and made some donation(people will make donations if the plugin was useful to them) A donation button wont decrease or increase ratings
I don't think it'll affect your ranking. People do click on Donate buttons/links. Just don't expect a whole lot.
It won't affect your rankings, but it is surely worth putting the donation link on there and in the plugin documentation. Another method I've seen used is to develop some extra features that are only available to people who donate.