I find any floating UI element that stays in the same place independent of how I scroll obnoxious. It's not how I expect, or want, webpages to behave.

They're pretty annoying. If they want to get feedback, maybe make it prominent on the front page, but to have it right there on every single page - occasionally covering up other things - it's really obnoxious.

It depends on the current state of the project I guess. It might be quite important that your visitors quickly spot the feedback-button when they have not yet discovered the full value of the service provided, IE when there's no incitement for them to scan for a way to send feedback.

In a later stage when feedback from users -- as opposed to visitors -- is more important the feedback-button could move down into the footer instead to make other calls-to-action more prominent.

Having that said, I'm also a little allergic to these feedback-buttons.

Also in the allergic-to-feedback-buttons camp. To the point where I'm starting to block them.

If I really want to give feedback, I'll look for a "Contact us" link, not something floating on the left or right side of my browser window.

I developed a simple webapp that generates jogging routes that come back to their starting point.

I wanted to know what functionalities I could add to make the service more useful; since services such as Get Satisfaction start at $19 a month, I developed my own solution (a very simple one, but truly independent of the source website, so it can be deployed on other sites).

The button is named "help us help you" which I thought was cooler than "Feedback".

I'm sad to report, however, that in the week it's been up, it's never been used by anyone... Maybe I need a feedback button to gather feedback about the feedback system?!?

For those interested, the jogging service is here: http://tjp.adgent.com/

Consider that most people don't expect a UI element to appear on the left hand side of the page, completely removed from all other UI and text. Most users are used to scanning the part of the page that already has text. Also consider that the text is vertical, so it's a little difficult to read.

I think people are tempted to use these feedback buttons because they break normal expectations. By not being a normal UI element, they draw attention to themselves - in theory. The other side of this is that by breaking expectations, some people may not realize it is a UI element.

Of course, an alternative explanation is that your users did not have anything to say.

It's a result of a strong campaign by http://uservoice.com. They've been pushing hard for the past 1-2 years and, if you were watching carefully enough, you could see those buttons slowly but surely appearing on more sites. They've simply reached a tipping point now so you notice them. It's somewhat akin to seeing a specific car model more often if you own the same model -- once you notice a pattern, it's difficult to un-notice it.

I like the UI. I dislike the UX, or rather what the button does to a site's overall UX.

Maybe I am showing my age here, but years ago we had a link in the footer right next to "contact" and "about us" called "feedback. And you clicked on that link, submitted your feedback and it worked fine.

Does a feedback tab really need to be positioned so prominently on every page and popup in a modal DIV using Javascript? My feeling is no, a simple feedback page is fine.