That gun is a "compliant" version... (Anybody else think "compliant" sounds like it belongs on another sort of forum?
It certainly has a built-in trigger guard, while the earlier M&P15 models had a separate trigger guard just like the M16. I bought the first M&P15 Tactical I found here in the Seattle area and have put on the MagPul trigger guard. The .22 rimfire and "compliant" versions seem to have the solid built-in trigger guard. Interesting.
Makes me wonder if S&W is switching them all over to the built-in trigger guard.