M&M 1st ed. vs. 2nd ed.

[Geesuv]

Yesterday, I bought a copy of Mutants & Masterminds as I've been intending to run a superhero game.
Today I discover there are two editions and I have embarrassingly purchased the first edition.
Before I go to the bother of returning the book I was curious about the differences between the editions. would anyone be able to tell me if there are there any significant changes in the rules and whether this is for better or for worse (and in the end, is it worth the bother of exchanging it)

Thanks a lot

[Pauwel]

I'd recommend getting the second edition. The first one would be a smoother transition for D&D players, but other than that I don't that it really helps the system to stay as close to regular d20 as the first edition does.

The difference between the two is that the 2nd edition is more radical than the first; your ability scores don't affect your attack/defence stats, for instance (this way you can have a character who's extremely strong without necessarily being more accurate than, say, a world-class martial artist). The second edition is, in general, also more versatile in its building of characters and customisation of powers (particularly if you buy the Ultimate Power sourcebook).
And of course, it does away with the monstrosity that is multiple attacks. (It's a monstrosity in M&M because of the way the damage system works).

[Nerd-o-rama]

From what I've seen, the only notable advantage first edition holds is much better artwork. Second edition seems to have a better sense of the design intent, which is inter-player-character balance and ease of power adaptation.