Yeah, though the playerbase itself is bigger as well - just look at the amount of raid bosses available on both versions.
As for catching up, I have a feeling that Nutaku's development/translation team may be too small (or not organised well enough) to keep up with the updates. This results in incomplete or bugged updates, as we all witnessed. This in turn may result in the time gap becoming bigger.
I also like the DMM version more and would probably limit myself to it
if I didn't have a sentiment to the time I've put into my Nutaku account. 