Additional things to point out is how well the MP site has been developed. Very nice interface.
Purchases deliver to a special folder in your inventory.
Content creators can opt to have real money go to their paypal account, or to the Kitely money, KCs...which can be used to buy content on the MP and even be used to pay for land...which is the least expensive of any commercial grid also, and includes more innovation in OARs upload/downloads [thus you can finally save your region in a file on your computer, no lost work, ever againm due to grid errors or account access removal].
I expect that now it is live more people will finally see the value in putting content in.
I already made a few purchases-))
Other than the SL MP, the other markets have been building for some time, and Kitely has already launched with a good start of content. Tie in the proprietary Export ability [opt-in] and the future launching of Hypergating ability, this grid is really going to do well.
Already it has more regions than any other commercial grid, by far, other than SL.