I see/hear DADGAD tuning being used frequently among the trad Celtic crowd, and I have played with it myself - but I cannot say find it attractive for my playing style, and tastes. I do enjoy the sound, and the options - but I prefer the 'rounded out' sound of standard tuning.

I sometimes use an open D Major tuning (DADF#AD) and frequently drop my low E to a D - but I suppose that reflects my American folk roots, more then anything.