ScreenshotShareSheet cydia tweak allows you to share a screenshot immediately after taking it by displaying a share sheet similar to the options in Photos.app.
owever, it goes beyond this, easily allowing you to open the screenshot in any app capable of handling image files. (iFile, Photoshop, Dropbox, etc.)
In addition, ScreenshotShareSheet contains a setting to block screenshots from being uploaded to Photo Stream.
Please note that other tweaks related to screenshots may conflict with ScreenshotShareSheet.