Clay provides a short rundown of some of the sites out there offering link management services. I recently tried one of these services "Furl" and I'm intrigued, but the jury is still out in terms of long-term adoption.
Here's why I like these services:
I often find myself reading a site and thinking- "I really want to come back to this, but I don't want to blog it, or add it to my bookmarks (which I never use anyway)." These services give you something to do with that link.
Often, they allow you to click a button (sometimes a "bookmarklet") and add the link to an online space for future reference. Quick and easy.
Furl allows you to categorize each link, rate it, and add comments and keywords for future reference. When I need to find that page again, I consult my Furl page.
The cool part, at least for me, is that this information also become public- and it can be subscribed-to via email. So, I subscribe to a couple of other peoples' Furl sites to keep up with sites they are referencing. Here's my Furl page.
In many ways, I see these services as an easy way to have link-blog. Whenever I see an interesting page that I don't want to blog- I Furl it.
I'm trying it out, but I'd say my chances of long term usage are 55-60%. If it does fly- I could see adding a link to my Furl page from my normal blog.