I don't think it's a game changer completely as for those who are diehard poser users will continue to use poser. You are content with what you have and great. BUT, those who are on the fence and hovering as to which way they will go, may jump into DAZ's garden. Also, newbies who weigh up the two programmes are more than likely go grab the free one.
At this moment in time, they haven't stipulated if it will be necessary to have the clothing as conforming or a prop or if both will be allowed. Personally, I hate weight mapping with a vengeance and probably will have me tearing my hair out if it HAS to be conforming. It works perfectly fine with a lot of garments that don't need pinning into place like my dress above. And if it needs a slight pinch in ( eg the waist) there is an expansion-contraction ratio setting which shrinks or puffs out that area (Surface/material zone)
Some things I've noticed which I think is an improvement over poser cloth room.
1. sims are faster
2. cloth properties can be saved out
3. no poke-throughs, I've draped about a dozen times and not spotted one pokey.
4. Can turn dynamic strength off or down for specific surfaces, ideal for belts or basques where the draping is required for other parts of the garment.
5. not tried it yet but multiple layers in one garment will drape okay without pokies, will test that out later with my peacock dress and overskirt
Downside -
1. It doesn't have constrained groups, so suppose that's where the conforming comes into play and you can remove or reduce the dynamic strength on certain surfaces. (IE turn dynamic strength down to zero for belts. they will continue to conform, whilst the rest of the garment drapes around it. Hence, most garments will probably need to be conforming (GRRR WMapping!)
2. No morphing tool to smooth anything out - however, it does have smoothing modifier which you turn off during sims and turn back on again afterwards. Plus there are no pokies so no need to sort those out with a morphing brush.
3. Long garments that hit the floor will need a ground plane added to the scene or it will drape through the ground shadow. If I make anything and sell it, I will add an invisible plane prop as standard. You just have to remember to load it or it will drape into the ground and beyond.