I think counting days is a great way to stay sober, if someone has the power to keep themselves sober that way.
As an alcoholic, counting days never did much for me other than serve as a countdown to that day I knew was coming sooner or later - the day I'd not want to but pick up a drink anyway.
Best way for me to celebrate my sobriety is to help someone else get some, not to yell from the mountain top how great I am for hitting x-days or y-years.