Well for those of us who were looking to get to Plat after losing the temp SPG Gold match to Marriott Gold benefits the spend on your existing personal SPG card this year can help. I just checked and see I have indeed hit the $75K so far this year so all I would need to do is upgrade and then I'm a Plat.
I'll do it because of of my upcoming travel certs and some points in my Marriott Account.
But when all the points are gone and the $450 renewal comes up I don't see any reason to keep any of my Chase Marriott or SPG cards.