Though I do think that Linux is a good OS which trumps Windows in some ways and FOSS is an honorable thing to believe in, the main reason why I switched was because my 5 year old video card died and Windows Vista (yes, Vista) finally bailed on me. Maybe playing SC2 and Dota 2 finally took its toll, maybe it was because of poor ventilation — who knows.
I really didn't want to buy a new video card just for the sake of being able to play a few games over Christmas break though which is why I decided to just wait it out and install Linux Mint (Ubuntu wasn't my cup of tea) until I have a new PC.
To it's credit, Linux Mint was really easy to install and, as compared to Ubuntu, it looks and feels a lot like Windows. It was also refreshing to be able to customize the desktop environment. Personally, I'd be fine using it with no Windows dual boot, soon I might give it a shot for gaming.
I really thought about going yolo and playing and downloading Dota 2 with no video card then I found out that my processor was an Intel Pentium D (lol) so I just gave up and accepted that it wasn't worth it. I'll miss playing, but at least I have Twitch streams to get me by until summer comes.