I have immediate needs for this type of feature. We would use it for events, to keep sales people updated, to support teleprospecting efforts that are not integrated with SFDC, etc.
This is something we've been looking for as well. If a sales rep gets 80 leads from an event or tradeshow, they want a general report or summary (like a smart list export) rather than seeing 80 email alerts hit their inbox. Looking forward to seeing a smart list subscription on a future Marketo release roadmap...or at least some other automated solutions.
This has been floating around for awhile now, does anyone know if this is being considered? Really getting a lot of requests for it. Some of our folks are considering other alternative to Marketo if this does not happen.