I just did a little back of envelope math and Hilton has really screwed up here. I use my Amex Hilton card and can earn 3 points for every dollar I spend. So a Category 7 hotel now costs 50,000 points. That requires me to spend $16,666 to get a free night there. But I can earn $320 cash back with a couple other cards. Except in peak season - when it's hard to get a free room anyhow - very few Hiltons cost more than $240 a night. And the math even gets worse the lower down the category chain you go. Obviously my situation is unique to me but I'll start putting my charges elsewhere. I charge $1 million a year on my cards for my small business. There are plenty of cards out there that want that business.
P.S. One exception may be if you are an American and want to use points to stay in hotels overseas. If the US dollar declines then it will at least be a better deal for us.