I'm sorry, but i think this approach is a bit wrong, because it doesn't emphatize the fact that games with more votes have a more precise score.
Thanks for the feedback. The goals of IMDB ranking are a lot different than ranking jam entries. For a jam you have to be careful about giving an advantage to popular games because it makes it impossible to compete if you don't have access to an audience of people. IMDB doesn't really care about this issue, they are happy to show what is both popular and highly rated because it boosts conversion rate on their list.
That being said though, I think using Bayesian average is a good formula, and maybe will be added as an option for future game jams.