The bearpit was a place for ads that didn't conform to the normal rules. Pretty much for those who were too lazy to post pictures, or whatever. The marketplace is much better with good looking ads that conform to a set structure.
I think the main reason people want to allow comments back is because of all the fun that was had dogging and degrading people's threads. Some posts turned into a circus and were fun to read and participate in. All in all, none of the comments helped sell items or contributed to the forum in a positive way. That's why comments were disallowed. If a seller's ad is descriptive and has all the proper information, the only discussion should be the price and where to meet, and that should stay in PM. Comments that would be used for questions only are silly. If someone has a question that wasn't answered in the description of the item being sold, it means that the seller did not do a good enough job when posting the thread.
If we allow comments in the marketplace again and crack down and say they can only be used for questions. No saying "nice gun". No comments other than questions if you are interested in buying the gun. The circus will not be back like it was before. Most people will use PMs if they have questions anyway. I don't see much changing from the way it is now, except maybe people will ask questions via comments occasionally. If someone were to post a question on a thread, we would not allow the OP to respond to it as it would get in the way of the bump rule, which is to ensure the marketplace is fair to all.
We have discussed this issue in great depth before, both publicly and in the internal mod forum. Pretty much it comes down to people wanting to be able to comment on threads because it was fun in the past. If we were to allow it again, it would not be fun for anyone. It would be to help people sell their items quicker and more efficiently. Previously, the marketplace was fun and people were commenting left and right on posts, commenting on how unrealistic peoples' prices were, and etc. All in all, that type of discussion did not help the seller at all. Often it made the person look bad and they would leave the forum all together. It was not a happy, fair, selling experience. That is not what we want. The marketplace is what drives the initial traffic to this site. People come here to buy or sell things and THEN they decide to participate in the rest of the forum. We have plenty of statistics that prove this.
So, if you guys ABSOLUTELY want people to be able to ask questions about an item in the marketplace, I could be convinced. I just don't see that being the urge. It is super easy to PM people. Most people don't have problems with PMs. Hell, a majority of the people who use the marketplace probably don't care at all about comments. If questions need to be asked, it means the seller didn't do a good enough job initially...so if they get lots of PMs, it is their fault.
I withdrawal my original suggestion. Leave it just the way it is.