Smith and Wesson did a real solid to the consumer on this one. Unlike future generation pistols we have seen from other manufacturers, all prior accessories from the M&P line still work. Yes, it is backward compatible. I tested this myself on magazines and holsters. Magazines still function flawlessly, and visually are indistinguishable from the 1.0. My Safariland retention holster holds the new guns just as secure as the old one, no problems. It is really nice to be able to buy a new gun without needing to invest in a pile of adds-ons, when you already spent the money once.

Yes, this is absolutely compatible

According to multiple sources the 2.0 DOES work with the original version magazines. Happy shooting.

Yes, the m2.0 is backward compatible.