An unofficial but neigh-undisputed pattern that appeared here in gaming is tagging questions with the name of the game they are concerned with. Some questions concern more than one games while others concern no specific games, but the overwhelming majority is about a specific game.
This is absolutely great - very easy to just add all the games I own to the "favorite" list - but using regular tags for this carries some problems:
The threshold to create new tags is 150 reputation - this may be too low for general tags but it's pretty high for game tags, since new users that want to ask about a game nobody ever asked about before cannot tag their question appropriately. Considering we cater also for old and/or unpopular games and that hundreds of games are released each year, this is a problem.
We already occasionally encounter a question in which the author asks high-rep users to manually add a game tag because she couldn't, and as the site grows larger this will become less scalable.
Tags with only 1 question expire after a while and are removed. This is a bad idea with game tags! I've already seen some old questions that were not tagged with a game name, although originally they had this tag.
Sometimes it's not clear a tag refers to a game name. Is colonization a genre, an action within a game, or a game name? Turns out it's basically all, so we really should reserve it for the game with this name, and making the tag look special would encourage that.
Right now the most popular tag is used as the first word in question page title. This leads to questions such as "pc - how do I kill the orc chief" rather than "orchunter-3 - how do I kill the orc chief". The latter is more informative and much more Googlable.
So I propose a new tag type with a lower rep threshold to create, no expiration and different visual appearance, which will only be used for game names. If a question has only one such tag, it will also be used as the first word in the page title.
I'm not quite sure how these tags will be created or maintained, though, just throwing out this idea.
I have a strong feeling that without something like that, the amount of questions requiring retagging to add the game name, and the amount of question that end up being untagged and forsaken, will rise over time. This will also make our site friendlier to new users (it's clearer a game tag should be used, it's easier to understand what tags are game tags, it's easier to find questions via search).