Seems like this week is an Acrobat week. So here it is my tip of the week.

Right click on a raster image with TouchUp Object tool (last icon in the Advanced Editing Toolbar) and choose "Edit Image..." to edit the raster image in Photoshop, or right click on any vector object with the same tool and choose "Edit Object..." this will edit it in Illustrator. Depending on where you have right clicked it might say "Edit Page ..." this too will open Illustrator.

Once you have finished editing either the image or vector object close the appropriate window in either Photoshop or Illustrator and save when prompted to do so this will automatically update the PDF.