Am personally still using GMS1. It still works perfectly find for Desktop and HTML5, which are my main platforms. Although I do agree that GMS2 looks much cleaner, and appears to be an all-round better product, the ~$250 price tag for the two modules isn't something I'm interested in perusing right now. Mostly because I can pick up languages quite easily, and there are many (free) multi-platform languages.
So to summarize; I use GMS1 daily, mostly for hobby programming. I don't see the need for me to upgrade to GMS2, because I can achieve everything I want to in GMS1. If I were going to upgrade, I'd be spending ~$250 for a better looking version of the exact same thing (in my case. I do understand that GMS2 has a lot of useful additions, but I don't think I'll ever come around to using them, and if I REALLY needed them, I could probably come up with a GMS1 alternative).
GMS2 is fantastic, and I love the direction YYG is taking the product in... but I can't justify ~$250 (as a hobbyist) for something that 'looks better.'