When answering questions on Stack Overflow, even if they don't have one of your favorite tags, it seems that you are subsequently presented with more questions on similar topics. Say I'm answering a Python question, even when the python tag is not part of my favorites, then it seems that the questions shown to me on the front page include more Python questions.
Is that the case? Are questions somehow filtered based on our most recent participation within a tag as well as our favorite tags?
Yes, there is a component of your most active tags in the homepage, even without using favorite/ignored tags.
I don't know how significant it is, and in any case, it's best that you fine-tune that list using favorite and ignored tags.
The questions on your homepage that are labelled "interesting" are indeed related to your participation. There is a feature on Stack Overflow that calculates the questions that will most likely be interesting to you in the future. You can see how your participation in various tags affects the questions being displayed on the homepage by looking at your Tag Future report:
There you can see a breakdown of the tags that Stack Overflow thinks that you will be most likely to be interested in. The questions on the homepage are filtered by both the favorite/ignored tags and the results in the tag future report.
