On the recipient end, what I'd like to see is some kind of central place I can go to which stores all the links people have shared with my email/FB profile/twitter etc. I can then sort through the list by date, category or whatever. If I don't have an account already, I link my email/profile info and it shows me the stuff waiting for me.

Obviously this would require some centralised service and for all sharing services to integrate with it - so perhaps this isn't much use. I'd certainly find it useful though. All these links pass me by if I'm busy.

I second this but I'd love to sort/filter links by quality and/or relevance. Some posts get superseded quickly (drop in relevance) or are debunked (drop in quality) over time so bookmarks should not be just collect-and-forget.

I hope Avos.com is reading this stuff.

Many people have actually said they need to find or remember many links or pages they have seen or opened before, but have not manually bookmarked. So you use case makes a lot of sense.

I think often I just want to let people know that I stumbled upon something; I don't really care if they actually check it out or not.

So, I don't quite like the FB way of listing all my links as posts. If it would say something like "<Person's Name> has stumbled upon 5 links today, click [here] to expand", I think that might be better.

I don't have a stumbled upon account (and I'm not entirely sure how that site works).

Something like Facebook shows album photos may be? Thumbnails next to each other, with a headline like you suggested saying how many you have shared per day?

Also I feel sharing should be one-click, something like Google +1, without the need to fill any status/heading/description/tag fields.

The problem with links is quality and structure. If you are just wasting some time on fb you don't need it, but if you are doing a research this is rather useful. Yet, nobody does it.

I have been learning web development in python the last months and what I am missing is a good way to keep truck of my sources and to share also. What if somebody just learnt the same thing and has a handful collection of links? No way he can share.

Not just link sharing, all kinds of archiving job are still difficult. Categorization by keywords labeling forces you work like a libarian. I usually don't remember what tags I used the first time and can't find what I want.