PictureFrameCenter is a Cydia Tweak/Widget which will add your photo slideshow to the Notification Center. If you are using Dashboard X you can, of course, put this on your Springboard and watch your photos go by as your scrolling through your pages. You can adjust the slideshow by using your standard Slideshow settings under the Photos tab. The Tweak does have a tab which pops up when you tap on it allowing you to skip photos and pause the slideshow. Unfortunately this part of the Tweak isn't working too well. Hopefully we'll see an update, PictureFrameCenter can be found for FREE under the Big Boss Repo.