I mean, a way to "follow" a especific user (an analogy could be mark a tag as "interesting"/"ignored").
Is this possible?
You can follow their RSS feed. Scroll all the way to the bottom of their user page. The RSS link is on the right.
A way to favorite or follow track users would only be a way to inadvertently game the reputation system solely based on subconscious human nature.
People with lots of followers would get even more up votes from the acolytes no matter how flippant, trivial, complete and incorrect their answers might be.
People with no followers would most likely get ignored even with better more complete and accurate answers.
This would turn the reputation system into a popularity score, more than it already is.
The inverse is also just as true, create an enemy and they could more easily follow you and serial down vote everything you answer or ask. That will make the sites better how?
I don't want to have to manage yet another list of people I don't want tracking me, I don't want to manage yet another list of people I have to constantly respond to requests either.
There is already this tendency for new users to treat all the stackexchange sites as discussion forums. Nothing should be done to encourage this behavior and increase the load on the community and moderators especially to police questions that clog up the works.
It would also signal a similar shift in policy to long existing members as well.
The RSS feeds already do what a favorite would do.
Use an existing 3rd party aggregation site like Delcicous.com to bookmark these feeds and aggregate them and publish and share them. Use Pinterest or Bo.lt as well?
A long-time-dead question, but I think it's worth the mention:
Unlike the others around here, I still think the usage for this is sound and well-founded, so I created a browser addon that highlights posts by your favorite users.