Mutants & Masterminds: What's the Deal?

[JeminiZero]

Is it balanced?

No. See this essay for more details.

Is chargen quick?

Much like D&D, this will depend in part on the player's familiarity with the system.

For beginners? Probably not. Fortunately, the core rule books come with some premade builds for a quick start one-off (although some are inaccurately statted IIRC).

Do the fights run smoothly?

Reasonably so I would think. Practical combat is less math intensive than D&D, mainly because there are no 10s of d6 damage die that you have to add together. See below for an example of how fights progress.

http://www.atomicthinktank.com/viewt...406527#p406527
http://www.atomicthinktank.com/viewt...408363#p408363
http://www.atomicthinktank.com/viewt...445048#p445048

Are adventures easy to design?

Yes. Mainly because the GM does not have to figure out loot.

I'm aware that it's a superhero game, I know that it's loosely based on D20, & I've heard it called teh best game evar. So what makes it so cool?

Mostly because the system is sufficiently diverse to simulate virtually any setting.