I second the question of what games use this sort of feature.
My comments here are going to be strongly opinionated, and do not necessarily justify anything. And so with that out of the way…
As soon as I reading things like “…minimizing the game”, I start shuddering in horror at the whole idea. From a UX stand point, (especially) when my game is full screen, the last thing I want to see happen is to lose focus of the game window – this completely ruins the experience of immersion. I’d much prefer copy and paste of the URL to open a web browser or what not explicitly. I cannot think of any use case off the top of my head where I find the lose of focus appropriate, other than (of course) OS-level events. In other words, I strongly prefer being in control of explicit focus changes of my game.
I see the counter argument being made where not having the game auto-minimize or what not and open the program automatically could be seen as less user-friendly here. I’d love to hear your own opinion regarding this? (Am I the only one that feels strongly about auto-focus lose?)
I do, however, feel that it is OK for a mobile platform to do so (minimize / lose focus of the game to do another task), perhaps because the underlying platform is fundamentally different, and/or I don’t have 15+ years of habits formed using the platform?
In short, I’d love to hear about your feelings regarding these sorts of UX issues – hopefully without inciting a flame war!