Since we also created the helpful answers feature I'm sure we can find a way to add thumbs
However it's really broader than that. A review is naturally biased by the person and their relationship to the object. Someone who eats at 5 star restaurants and goes to a 3 star diner is going to have a different read than someone who eats at home and goes out for the first time in a year. That's not an easy solve, heck, the best solution right now is to aggregate "about me" tags with reviews but we're thinking about what could be done knowing the detailed nature of a forum to go deeper and provide not just acceptance of a review, but context.