SALES can mean you simply fooled people into buying the album...it doesnt mean people liked the album. With good cover art, as lil shrink wrap and a fast line you could move 10,000 blank CD-R's if you're smart about it...
That doesnt mean 10,000 people enjoyed the album,or would ever buy another one from you again.
Your song could get 10,000 plays on Myspace, that doesnt mean any of those people enjoyed it or are now your fans.
FANS = returning customers happy with their initial purchase and anticipating another one soon.