I recently stumbled upon Google Spreadsheet’s worksheet syndication publishing feature. Basically you can publish your spreadsheet as a RSS/ATOM public feed. Also using Spreadsheet GData Client API it is possible to add new entries to your spreadhseet. Leveraging these abilities the possibility of using Google Spreadsheet as a Personal RSS platform seems very straight forward.
Basically one can create a worksheet and set the publishing option to output RSS (or ATOM or any format of your choice) and select an appropriate publishing frequency. Once this is done whatever you add to your worksheet is available for anyone who subscribes. Also there is an option to customize and publish a select range of cells and not an entire sheet.
Now it is possible for Clickables (Google Gadget that I developed few months back) to use spreadsheets and provide persistence bookmarking of shared links. Also, integration with Yahoo Pipes! can bring about a lot of data mashup feeds.