Well, I was really hyped over MAG back in August 2009, that I even spent days trying to get in the closed beta and I ended up succeeding. The game really promised a unique gaming experience to every one who loved FPS games. However, the game had so many flaws.
To start, the game just concentrated on the "256 Online Players" in their advertising campaign, not mentioning how much amazing things does MAG have other than this, like the ability to choose your PMC, and to create your own character. Yes, I know these were advertised, but it was too late.
Beside this as a whole, the game didn't have anything that made the casual gamer go back for more, I hate saying this, but it was un-balanced, I've been in first closed Beta, and in the first few days, the game was extraordinary amazing, but after 4 months of the retail game being out, the game started losing it's fun, I'm either playing with people who think it's real war, or just some noobs who aren't willing to listen to me in the mic, they are just running around thinking it's COD. On top of all this, communication is essential for this game, regardless of that, zipper never made any efforts in putting a MIC in a special edition or anything. ( Like a MIC only mode )
The other thing that let MAG down was comparing it with extremely solid franchises such as BF and COD, which put this huge title at a huge dis-advantage, it wasn't made to compete with BF or COD! It was made for a unique gaming experience.
One of the others things I hated was the stupidity of making SVER the OP of this game, and yes OP. Anyone who played this game for some time would tell you stick to SVER. Why? Their maps gave them huge advantages, and when Zipper patched it by making random maps, it was too late....again. Moreover, they added the clan war system in like September 2010, 9 months after it came out. So every clan out there lost interest and moved to another titles.
In my opinion, MAG is a very good beta for enormous future like title or a sequel for it. Zipper definitely learnt alot.
N.B. It's normal not to hear about a game that's been out for more than 2 years, especially when it's an online FPS, and not an elderscorlls/GTA title.