Bravo - that is really something. 5000 of us contributed to MMS and that number is still growing.
Personally, I think this is the most important task for MMS in 2010 - to gather as much materials as it is possible. People are choosing other sites only because they have bigger amount of stock. Over 8000 materials is a good score, but still not too many, comparing to 400k that SXC has. I think 50k or even 100k is a minimum.
And, of course, the problems with search engine. "Car" is one of the most popular image people search for. And here it gives NO results. No wonder people are not tied to MMS...

