We ran a beta for a month on this feature and received great feedback. We are working on incorporating the feedback into the product and planning to release it in October.
Please feel free to reach out to me directly at mjeswani@marketo.com for more details.
It would actually be quite handy to be able to subscribe to the members of campaign report.
For events rather than having to go in and export a list of what status each lead currently has RVSP, declined etc just get that emailed to me and other people interested on a daily basis.
Just officially confirming here, we are releasing 'subscribe to smart list' in October 2015 Marketo release. Thanks to all your support & feedback during the beta testing. Appreciate your continues help in improving our product!