Cassini is already on its way in to a close, 500-kilometer encounter with Dione -- it's less than four hours away now, at 17:52 UTC. Here's a photo of Dione and Saturn that was taken a couple of days ago:
The science plan is absolutely packed, with CIRS, ISS, and UVIS trading priority continuously for hours and hours, and VIMS riding along the whole time. As with the Hyperion encounter, they are doing mass determination experiments with the Radio Science antenna for a couple of hours on each side of closest approach. There are a bunch of fields and particles observations as they fly through the E ring. At closest approach, they give up on pointing, and give control over to the Radio and Plasma Wave experiment, with ISS snapping pictures willy-nilly. The crescent outbound view should be lovely and lit by Saturnshine. And, finally, they'll get their best views of Telesto throughout the mission at 20:26, from a distance of only about 10,000 kilometers (which gives you a resolution of 60 meters per pixel with the cameras).