Speaking from my own experience, I find that my interest for questions is often quite temporary.
Sometimes this is because it a question I asked which I do not yet have an answer too, other times it can be a question that is still being discussed.
Whatever the case may be, I find it very hard to actually get to the questions I am currently interested in FAST.
Usually, I go to my profile page and either browse my own questions, or, if the question was asked by someone else and I participated, I look around in my recent activity or favorites.
In my opinion, there are too many clicks involved to get where you want. What I'd personally like to see is a function to mark a questions as "interesting". This mark is entirely personal and should not be shown to anyone else; interesting questions would then show up in a compact list on the top right of the website, just like the tags block, for example.
Just to clarify: I believe the favorite mechanism works fine, but serves a totally different purpose, namely to store questions that interest me for the long term.
I am looking for a way to easily stay up to date with questions that interest me now. My list of favorite questions is not private, is quite bulky and is hard to reach.
What are your views on this?