It has come to my attention that there appears to be a WordPress bug regarding the saving of custom fields. As custom fields play a major role in the Market theme, I am suggesting that if you are a current theme user who has not upgraded to 2.5 yet but is considering it, please hold off until this issue is resolved. For those interested in purchasing the theme, you may still do so, as this issue is (99.9% sure) on the WordPress end and not the themes end. Regardless of what theme is being used, WordPress should still be saving posts and all the additional meta data. And this only came about with 2.5, so something is wrong here.
Keep posted on the progress of fixing this bug here. I will keep everyone posted with what exactly is going on with this issue in news updates as well.
Thanks for understanding.
Update: This is a known WordPress 2.5 bug which should be fixed for 2.1. A temporary workaround has been found. Read all about it here.