Steam is following in the footsteps of so many other online shops by allowing its users to review their purchases.
Back in 2010, Valve introduced the Recommendations system and the newly announced Steam Reviews is said to be an evolution of that. Valve announced that it’s currently in beta and they will be evaluating how their user base takes to the rating system.
You can submit a review of a game once you’ve played it via your account and your playtime will be displayed alongside the text of your review. Similar to a service like Amazon, you can then click a button to say whether you found a review helpful, or not. On top of that, you can add your two cents by commenting under a user’s review, itself.
The Metacritic score will still be displayed on game pages — Steam Reviews will just be in addition to that. Also, abusive reviews can be flagged by users, if they contain anything that’s deemed to be inappropriate.
Valve has stated that they are considering implementing a scoring system for Steam Reviews, but want to gather data from this beta process, first.