A warning for those of you staying in Starwood properties in the US: some US hotels don't/won't post the 1000 CP points. For me, this has happened only around Chicago, were I find the Starwood properties to be lacking. But it might be a problem elsewhere, as well.
Otherwise, I'm quite happy with Starwood. Sometimes I'm automatically upgraded, other times I have to ask, and sometimes, there are none available. (At least, that's their story.)