I am curious why no one mentioned Capital One Venture where you can apply the points earned to any hotel - so the affiliation (or not) with a chain is moot.

I have lots of experience with Hilton and SPG (end up aggressively getting SPG points for a trip to Italy where they have a much stronger presence than Hilton) and agree that if you are starting out in anticipation of a specific venue, look at your hotel options first then choose a program.

I am looing at a trip to Portugal and although I have thousands of points with Hilton, SPG and Mariott, I found that there are "alternative" awards through American Express MR that will give us 5 star stays at properties where we could not use our other points. It would also give us an opportunity to stay somewhere that we otherwise would have "overlooked" because they weren't Hilton/Starwood/Marriott.