The main problem with IMDB ratings is that people often throws 10 at shows just because they like them. So yes, I enjoyed Gotham, but rating it 10 is just as absurd as some people rating it 1. I think that the most accurate way of rating shows is not going from 10 and down, but to start at 5 which should be considered average.
Now Gotham is clearly above average, but it's not without flaws. Most of the acting is good, in a few cases even very good, but in other cases really bad. And then there's the question about how the show holds up quality over 100+ episodes. As we all know most series show a decline in quality the longer they run, and Gotham is no exception. 1st season was very good and the 2nd and 3rd were pretty much ok too, but already in 2nd season there were signs of the writers having trouble coming up with fresh ideas, and that trend became more and more obvious as the show went on. Again, this is a show worth watching, but I think 7 is a fair overall rating.
