My Tweet Slidedeck was working fine, just noticed today it isn't showing up and it looks like it was one of the plugins I updated a few days ago, so I'm assuming it was something in the update. I had to remove it from my sidebar widget because it looks tacky to be blank on my site. If anyone is interested, until this gets fixed you can post up your Tweets via Twitter embed code: https://twitter.com/settings/widgets/new
The Twitter feed will take on the width of your sidebar, you only have to set height.
Hope this gets fixed soon: I prefer the look of the Slideck.