If it was such a big deal then I'm sure the band wouldn't have been touring for the last 2 years w/o him. Its still the same thing, band tours w/o Jeff. Obviously its a lot more of a different situation than before but that doesn't change that Jeff still won't be touring w/ them.
Personally I don't think it should go on w/o Jeff because he WAS Slayer. But its obviously not up to me either.