I was just putting together a test workflow for a custom list in SharePoint which uses the "Pause Until" action, to pause the workflow until a certain date is reached and then send me an email. However, even if I set the date to today, the workflow never fired.
A quick Google-search later, I find this post on the SharePoint Designer Team Blog, outlining a hotfix for timed workflows in Windows Workflow Foundation. Downloaded it, installed it, now my workflows fire!
My only problem now is that a new workflow kicks off every time I change an item in my list (which is just fine), but the existing workflows from previous edits don't stop. That's no good to me if I change the date that I want the notification email sent. I'll get a bunch of emails on the old (wrong) dates.
Anyway: If you're working on workflows that need to wait for a duration or until a certain date, then you need this hotfix. Go get it!