My site's performance woes are tracked down directly to the Sexybookmarks plug-in. Which is unfortunate because it's such a fantastic addition to just about any site.
It doesn't seem to matter how many 'shares' I've got activated; whether I'm in Beta Mode or not; Background on or background off. Every thing results in the same ugly outcome. My site takes about 1-2 seconds to load without the plug-in activated; with it active, some times a page load exceeds 20 seconds.
I hope the author will look and see what's going on and can hopefully fix it.