A similar bookmarking service that's been around for a long time is Pinboard https://pinboard.in/
* pinboard's blog includes financials https://blog.pinboard.in/blog/
* general advice to neither use nor run free services that don't have a business model https://blog.pinboard.in/2011/12/don_t_be_a_free_user/
* the great Delicious exodus of 2010, where pinboard acquired eleven thousand new users over a period of days https://blog.pinboard.in/2011/03/anatomy_of_a_crushing/
> On December 16th Yahoo held an all-hands meeting to rally the troops after a big round of layoffs. Around 11 AM someone at this meeting showed a slide with a couple of Yahoo properties grouped into three categories, one of which was ominously called "sunset". The most prominent logo in the group belonged to Delicious, our main competitor. Milliseconds later, the slide was on the web, and there was an ominous thundering sound as every Delicious user in North America raced for the exit.
> I got the message just as I was starting work for the day. My Twitter client, normally a place where I might see ten or twenty daily mentions of Pinboard, had turned into a nonstop blur of updates. My inbox was making a kind of sustained pealing sound I had never heard before. It was going to be an interesting afternoon.