Here is the main difference "If you don't qualify for Jr. VIP but still want to submit a thread onto the marketplace then Marketplace seller is for you." It allows you to start a BST thread if you don't have enough posts, but your thread must still undergo strict moderation/approval.
This can be seen clearly in the thread here: https://www.blackhatworld.com/seo/updated-bhw-member-levels.889577/
This explains it much more concisely and to the point.
I appreciate that!
You need to have 100 quality posts and be active on the forum for 60 days to be eligible for the Jr.VIP Membership. If you do not want to wait you can always go for the marketplace seller option instead.
Comments/posts/messages are the same thing.
I suppose you are talking about a marketplace thread. Once you've submitted your marketplace thread, you will receive frequent updates on the status via PM. If you have eMail notifications for PM's enabled as well, you will also receive a eMail once there Is an update for your marketplace thread.
