I think it just doesn't have the "stigma" with the "mainstream" public that it once did, and as a result of that a lot of people just don't really care if it is legal or not.  I do think, though, that it is very price sensitive and many will decide not to use the stuff produced by the companies included in the new ETF and continue to get there supplies from the vendors they have used in the past.  I once asked the great Peter Lynch what he thought about the market and he said:  I have two balls and neither one is crystal.  Same with me, but I am much more cautious than some in assessing the longer-term potential of these companies.