I love the concept. Lightweight, no JS, simple and compact add-on with optional widget. Unfortunately, not multisite compatible (except for blogs on a subdomain, won't show up for domain mapped blogs), the UI for customizing the links is buggy, and it adds "news" to the dashboard, which I hate when there is no option to turn it off in the plugin itself.
I can live with the ads for the other icon sets in the admin (even though the plugin makes it look like these come with the free version) and would probably donate if it worked. It just didn't for me.