1) Bring back tags. 2) Give users the option to set their "follows' to expire. Maybe you think I'm awesome. That's cool. Maybe two weeks later you're sick of me but unfollowing someone is more effort than it's worth. Have an opt-in that says "follow forever" and have it default to two weeks. 3) Bring back tags. 4) Give users the option to reject followers - rather than have it automatic, make it more like Facebook or LinkedIn. 5) Bring back tags.
Idea #2 is particularly interesting. I think it won't work as is because it's exhausting to be on a treadmill of constantly refollowing people. Some people may welcome the opportunity to revisit decisions and shop around, but I suspect it might be going too far for many people. (I'm happy to be persuaded otherwise; chime in in responses if you feel strongly one way or another.) The problem you're trying to address is that people rarely cull their followers. Every new medium gets users excited, but they end up following too much over time, swamping themselves, getting jaded, and leaving. I think about this every now and then; I even wrote about it 4 years ago: http://akkartik.name/blog/2009-05-19-21-30-46-soc The solution I came up with was to measure time in votes. I built a site that looked like reddit but was a feedreader under the hood. Users need know nothing about RSS or XML, they would just upvote and downvote the stories they saw. As they upvoted stories they were subscribed to the corresponding sites, but subscription wasn't a binary activity, you could be 'partially subscribed' to a site, and the extent affected how many stories from it you saw on your frontpage. When I built this, I saw something interesting. I observed many sites go through a common life cycle with their users. There'd be an initial honeymoon period where most articles were upvoted, and the site was close to 100% 'subscribed'. Then interest plateaued for a while at some lower level, then they lost interest, and a few downvotes brought it down to 0% subscribed, and they never came back. It might be worth reconstructing this life cycle here somehow. Just an idea to throw out there. To reiterate, I agree with the problem. I'd like to make hubski a site that doesn't fail from too much success, that can handle lots of people, or people subscribing to lots of people.
How 'bout "every time you vote on a link provided by someone you follow, that 'follow' is extended a set increment of time." Set "follow" for 2 months. If you share content that you follow, the clock gets reset as if you'd just chosen to follow that person. If you don't share content the clock counts down. No shares in two months? You no longer follow that person. 1 share after 59 days? You still follow that person for another 60 days.
'K, set it to "number of posts" rather than "time." If alpha0 shares 20 links and you vote on none of them, you no longer follow alpha0. If alpha0 shares 19 links and you vote on the 19th, you'll follow alpha0 - no matter what - until his 39th post. Certainly incentivizes you to only share quality content, rather than shotgunning every single Reddit link you find.