I picked up my M&P (M&P 45 w/thumb safety) right after my first armorer class (late '07). I ordered it and finally got it in early '08.
The trigger pull was at the high end of the normal weight range (which was 7lbs +/- 2lbs for the .45's). Mine averaged 8 1/2 - 9lbs, and the initial pull was a bit rough. One of the things about having been a long time revolver, 1911 and TDA (DA/SA) and "DAO-ish" shooter, and a firearms instructor, is that I adapt to the trigger of the gun I'm using.
In other words, once I got out to 25-50yds, I had to work a little harder to get reasonable groups, but the practical accuracy was there. I just didn't have the trigger to use as a "crutch".
The next time I checked the trigger on that M&P 45, it was a few months and more than 2,000 rounds later. It averaged 5 1/2 - 6lbs, and was smooth. It was pretty much identical to the same model M&P 45 another instructor owned, and in which he'd installed aftermarket parts (for a range gun).
Naturally, when a revised striker and sear plunger was available from the factory (part of the ongoing revisions), as an armorer I tried them in my own gun. The new striker spring/striker and sear plunger & spring brought the trigger pull back up to about 7+ lbs.
I've tried and used a lot of different M&P's over the 10 years since they were released on the market (Jan '06), and have been through the armorer class 4 times, I think (I have a number of different armorer certs for different guns, and I've lost count of all of them without actually counting them, but it's in the 20's). I learned I have another M&P armorer recert coming up later this year (after a 5th Glock class, since I counted those recently). I have no doubt I'll hear some new things about ongoing revisions of the M&P's.
The 9's & .40's have gotten a lot better and are more refined that the early ones. The company got enough complaints about the lack of feeling a distinct "reset", that they've addressed that in recent guns. (Give someone a semiauto pistol with a non-distracting mechanical reset point, and not everyone is happy about, it seems.
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They've also changed over to using the Performance Center sear in the production 9/.40 guns, and have tweaked the angle of the trigger bar cam, to not only keep the trigger pull within the current industry standard for duty/service pistols (5 1/2 - 6lbs), but to change the trigger pull characteristics and "feel". They've also revised the slide stop lever design to provide increasingly more inboard tension against the trigger bar tail, so it has more of a felt "snap" against the reset sear. (Lots of new shooters have become accustomed to the connector & trigger bar tail "slap" of the Glock design, and have come to expect it to be "normal" in other guns.)
Personally, since I'm not a "shoot-to-reset" target shooter, but a "trigger-recovery" shooter - (and since I shoot and have to train people to use different makes/models of handguns for duty & off-duty defensive roles) - the lack (or presence) of a distinctive mechanical reset in some particular gun or other doesn't bother me.
The M&P 45 hasn't yet received the same trigger treatment of the smaller framed M&P's, but I keep hearing they're working on it. The problem, as has been described to me, isn't to get the trigger light enough. They can do that, but it's apparently to make the improvements in such a way that they can keep it heavy enough remain within the industry standard for a duty pistol, in the larger .45 frame. They've made some competition-type 9's/.40's, with lighter triggers, but not any .45's. Maybe some increased market demand for competition-ready .45's may change that in the near future. Dunno.
Now, with the release of the Shield 45, maybe they've changed something. Dunno. The Shield armorer class is actually a separate 4hr class (prerequisite of the regular M&P class). The Shield is the little brother of the regular M&P, but I'm told there are a couple differences they felt significant enough to make them add a supplemental 4hr class for armorers. Haven't had a chance to go through it, yet.