The thing I really like about the sobi2 reviews plugin, is that it will send notification to the author of a listing when a review is left, regardless of whether they created a comment or a forum post. I am using sobi2 more as a download repository, so it is useful to have authors notified when there are comments on their listing.
However, there is no way for the author of a listing to turn this off. Also, the review plugin still sends out the notification email even if I set reviews to be moderated before being published. This might become a problem if the listings start getting spammed. I've already seen a bit of spam and I don't want to annoy the members of my site with the spam comments in their email. I wish it would only send out the email notification once the review has been published. I'd also like to see the Vote count next to the stars. Probably should submit these as feature requests. I just don't want to overwhelm the developers with all of my feature requests

I'm thinking about integrating the discussbot in addition to the reviews plugin. Since I already have a forum anyways, I'd rather use the discussbot than add another component. It integrates users' forum avatar and looks really good. Here is a list of the features with discussbot:
http://www.objectclarity.com/index.php?option=com_content&task=view&id=22&Itemid=46So, there is 5 star rating and email notification to author provided by the review plugin. And then there is the option for more lengthy discussions in the forums by members with the discussbot (when it is made compatible with sobi2). Actually, I'd be just fine with the review plugin only for sobi2 if it were improved some and could maybe integrate with either fireboard or community builder for displaying avatars etc.