Unless Marriott makes a huge devaluation to their rewards program (50-80 % bump in points needed) and completely messes up their customer service, I will prefer Marriott over Hilton or Starwood. I signed up for a Hilton Amex Card because I want a better credit card rewards program for everyday purchases and for the opportunity to get gold with Hilton. However, I am somewhat jaded about Hilton after reading through the long thread about the Hilton San Francisco's upgrade policy and Hilton's desire to upsell upgrades over rewarding top elite members. The last thing I want to do is get in a major battle with customer service over guaranteed upgrades. I also realize that Marriott's guarantee of concierge lounge access or a free breakfast is a big perk for me. I have stayed at properties where I can get a free breakfast on the weekends (even though it is not guaranteed in the T&Cs).
Point devaluations have occurred across all the major brands. I think Hilton did a good job of creating a new reward category. This gives them the ability to market a group of hotels as exclusive and charge more points for awards. They can bump up category 6 hotels to this new category and selectively devalue without changing the entire category and raising the ire of their customers. Devaluation is a continual process, and it is not going to stop. I cannot reiterate the point made by some that reward accounts are not savings accounts. You have to spend your miles/points knowing that there will probably be at least one significant devaluation every 3-5 years.
Having said that, I am still shocked at the relatively low percentage of guests belonging to Marriott Rewards at FS Marriott properties. I saw the number on a Marriott website for potential hotel owners, and it was around 50 % IIRC. People who do not use reward programs are subsidizing those who do.
I don't think anyone is thrilled to pay more for hotel rooms, but I see no compelling alternative for my travel needs. Again, everyone has different needs and experiences. I am not discounting the bad experiences that some have had with Marriott. For me, it has been a good relationship. I get the upgrades when I stay at the nice properties (so far I have been 2 for 2 in getting a suite upgrade at the Orlando World Center Marriott and have gotten nice rooms at Marriott Philadelphia West and the NYC Marriott Marquis), and I have not had any difficulty getting customer service problems addressed. I see the Hilton credit card more as a way to conserve my Marriott points for additional travel packages and sample the Hilton properties that stand out.