The more I think about it, the more S&W would have benefitted from going with a different trigger (and by "trigger" I mean that curved part that sticks out of the gun), since the M&P trigger looks exactly like the Sigma trigger, and no one wants that.
If that's not a testament to just how horrible the Sigma was, I dunno what is.
No, the triggers are not the same. Or, rather, the curved part that sticks out of the gun is the same, but the little metal bits to which it is attached are completely different. The M&P trigger is a million times better than the Sigma trigger.
Mike
PS Oh, also, the M&P trigger, out of the box, is kinda gritty and creepy. It's not bad, but it is also not great. It cleans up nicely through simple use, though. After about 2k rounds, mine is quite smooth. If you get a gunsmith to work on it, you can make it very nice indeed.