Since I can't stand to play D3 right now, I decided to do some WOW pvp. I did not buy MOP and havn't played WOW in 6 months and I thought I was done with WOW. However, I got D3 with an annual pass, so I can play WOW for the rest of December. So I got on WOW and did some PVP and had great fun. I love AV.
So what has Blizzard accomplished... getting me to play WOW again, making me at least think about MOP, making my open to buying a D3 expansion.
I thought I was done with Blizzard after the Starcraft 2 games, but they made me think about their other games. I'd say that's a success on Blizzard's part.