Sorry for the late reply, I hadn't seen your message.
I am a very new user of your program, and find that it is very good.
I wondered if it would be possible to add an option to the Netflix options to show whether the program has been viewed or not.
To show that you've seen a program, you have to rate it. For the TV shows, you can also rate the seasons or the episodes that you've seen by clicking on the number of episodes (displayed in red next to the title).
When you're not interested in a movie, you can rate it "not interested" to remove it from the suggestions.
You can also mark as "not interested" a series that you've started watching but you don't want to view more episodes.
I would like to remove series and movies that I have seen from view.
You can use the filter "not rated (not yet seen)", but indeed there'll be a problem with the series.
It's something that I need to improve. There are a several directions that I consider to explore:
1) add the value "series (some unwatched episodes)" to the filter "movie vs. series".
2) add the value "series (own some unwatched episodes)". (available on Netflix is considered as owned)
3) add an option to save complex searches and recall them with a single click. You could have a handful of searches for your Netflix needs.
4) create custom alerts, for example to tell you when a new episode will be aired on TV or when a new season is available on Netflix.
As you can see, my ideas aren't yet 100% defined. We can brainstorm the subject if you want.