Hearthstone in my opinion is an interesting twist on the tcg genre, maybe a new type of interface that corroborates with a newer kind of gameplay, some may say a bit more simple than say other classic tcg games like Magic. Regardless I find it an interesting game that you can play for about an hour or so.
It's a fun game, the learning curve is a little bit big, so a lot of people are put off by all of these complex cards and strategies when they look at the game. But in reality it's all about thinking before you engage into a battle, and doing some basic math (which shouldn't be too hard hopefully!)
A friend of mine is constantly playing this game. I thought about playing it, but I didn't have the time to do it :c Hopefully, soon I will be able to. The thing is that I've always been so bad for cards games, we'll see how it goes...
I've seen quite a few people play, but I never got into it myself. Friends post about it on Facebook all the time, and the LoL streamers I subscribe to frequently play when they're waiting for ranked matchups. However, I guess it has its appeal, and I'm glad it has such a dedicated fanbase. Unfortunately, I'm probably never going to be one of them.
I agree with you, an hour or so is the most I can get. But realistically, I cannot figure out the insane appeal that it seems this game has. I may be missing something, but where is it innovating?