As sources grow, aggregating content in for a site is becoming as important as syndicating content out. Although the aggregator module is strong, it could become much more useful if it was taken to the user level.

It would be great if users could create, edit and remove feeds from their own aggregator profiles, and optionally share the permission to view their aggregator with registered users or any visitors. I don't know where the CivicSpace Labs guys are at with their work on groups, but if it could be prepared for their success that would be awesome.

OPML in and out capabilities would be equivalent in coolness and utility to the new foaf module Bryght has created.