We can at least rule out FT-1DR working with DMR sets, because as they are currently spec'd and sold, it's just not possible for a FT-1DR to communicate with a MOTOTRBO/Vertex/Harris/Hytera set, unless both are using standard analogue FM.
I do hope Yaesu decides to embrace DMR fully and bring out Tier 2 sets (and repeaters). If they did they would not be going it alone and could lever off of the existing DMR networks and user base.
But... I fear they won't and instead will come out with a more ham-centric product.
The DMR specification for subscriber sets (radios) speaks to a numeric identification number, not alphanumeric, so id'ing radios by call sign (common in ham adaptations of digital over the air tech) can't be accomplished. The current DMR amateur radio network relies on cooperation and registration - send a note to a central authority to get back however many radio ID's one needs.
Judging from the Yaesu literature their first product implementation feels to me quite different than the DMR spec, although for future products it's conceivable they could build flexibility into the product such that it could participate in a MOTOTRBO compatible DMR network.
If they ham-ified the DMR spec for their own products then we'd see a balkanization of DMR-Commercial and DMR-Ham users, meaning the two would not be able to talk to one another directly, necessitating some sort of digital gateway product be developed.
Or they could roll with what already exists and works very well and join the already world-wide DMR networks and there'd be benefits to Yaesu in doing that given that currently the only suppliers (other than eBay sellers) of sets are commercial sellers and they are not well setup to deal with Radio Amateurs. Programming sets is complicated, best done at the club level rather than each individual, especially where Motorola gear comes in due to the complexities in getting the software in the first place. Vertex is easier in that regard.
If there was a maker of robust DMR Tier II gear and software, available from regular Amateur Radio supply channels, with simplified setup aimed at individual hams, that'd be very cool indeed.
Hey, a "configuration server", on air, as part of a repeater system, that broadcast programming packets such that subscriber sets could merely listen to an assigned frequency and be populated with the right info... turn a new radio on and within short order it is ready to go... yaesu should build those sets and that infrastructure.