I'd like to see a new feature introduced to ArcGIS Online that allows users to easily share AND update bookmarks between the web mapping apps created using this website. For instance, if I make a map (let's call this "Map A") with a number of bookmarks, I know I can duplicate these bookmarks by just creating a copy of the map (let's call this "Map B"). Easy enough.
BUT if I want to add new bookmarks or make corrections to the bookmarks in Map A, I'm out of luck if I want to have these automatically updated in Map B. It looks like the current process is to go in and manually tweak the bookmarks in Map B instead.
As a solution, perhaps introduce a true map template ability to ArcGIS Online for Organizations. All maps associated with the template will be automatically updated if the bookmarks in the template change, or other features such as the initial extent, base layers, etc. Give users the option to toggle on & off which settings spill down from the template whenever the template is changed. Anyone who has used templates in Macromedia/Adobe Dreamweaver software will know what I'm talking about here...