M1 and DVI are not the same, but very similar. M1 is more versatile than DVI in that M1 will accept analog and digital data/video as well as USB and I'm told it can provide low voltage power to an external device. M1 can be used with HDCP. DVI to M1 adaptors are available at most of the normal online cable retailers. We are starting to see a lot of PJ manufacturer's using the M1 standard because of it's versatility. Personally, I think it's fine for business projectors but I'd like to see home theater projectors stick with DVI.
htr