The Omni Group has released a significant update to OmniGraffle, its flagship diagramming app for the iPad. OmniGraffle 1.1 adds support for Multi-Touch gestures within the app such as the ability to select multiple objects by tapping and holding while selecting, two-finger rotation of objects and invoking temporary smart alignment guides while moving objects. The update also delivers improvements in performance, text editing and file handling. Several…