But I still prefer the Glock because of the trigger reset.
I like the Glock reset because it is really firm and obvious.
The M&P reset is very subtle and too gentle for me. Don't care for it.
The M&P's trigger reset is, I believe, very easily tweaked.
I dunno if the M&P will supplant the Glock, but S&W is sure going to give it a go. They're doing one thing that Springfield, at least, has not done: they are making a concerted effort to make inroads into the LE market. They're doing it in the method already mentioned: bulk discounts to LE agencies, one for one trades (give us your old handguns, we'll give you a brand new M&P), package deals (rifle and handgun), and marketing S&W as a one-stop-shop for your firearms needs. XD, I don't believe has done any of that, or if they have, they have not been successful. HK has tried, and been reasonably successful, but they tend to be a pain in the butt to deal with, customer-service-wise (nothing makes departments want to go elsewhere like being a butt about fixing your guns). S&W will bend over backwards for a department.
Glocks are good. They're firmly entrenched. However, I think the general message is that even if the M&P, or any other single pistol line, fails to supplant the Glock as "the" sidearm of LE, the days of Glock being unchallenged atop the duty-gun heap are waning. Many of the guns mentioned previously (SigPro, M&P, XD, HK, etc) are all quite good. As good as a Glock? That's for individual users to decide...but the proliferation of viable choices alone will eat into Glock's marketshare.
Mike