I check reviews on TA but regularly find it irritating when misinformation is stated as fact. I have found TA most useful if I am looking for somewhere special in a quiet corner of Europe but its usually quirky rather than luxury accomodation.

I read the usual glossy travel magazines and newsletters. I prefer Gallivanters to Harpers as I think Harper is more geared towards northern americans with an emphasis on the U.S. and its environs.
Although I have occasional business travel to the U.S., my main leisure and some business travel is to Europe and Asia. I think the advice I have received from Gallivanters for Asia in particular and Europe has been invaluable. The detail of each hotel and resort as described in Gallivanters is exceptional.

I enjoy CN Traveller as a flick through glossy and I usually find a few interesting points on various locations but it is 'lite'.
Flyertalk provides an incredible resource and if none of my previously mentioned sources were available, I would still travel well with the advice here. I like to dip into the other Travel&Dining threads and I have found interesting luxury hotels in the trip reports and individual country/areas.

A combination of all of the above mentioned sources keeps me a happy traveller!