On the Marriott forum we've started adding resort fee details (cost, what it includes) via wikis on properties where we know they've got resort fees. Of course that only helps folk who read about the properties on FT, but it does provide some info. It's interesting - some resort fees barely include anything; others include quite a bit, so what you get can really vary.
The big pet peeve (at least on the Marriott forum; not sure about Hyatt) is when the resort fee includes free internet, something that elites get anyway & yet the resort fee isn't discounted because of it.
Cheers.