Harrahs doesn't seem to want to talk about the 7-Stars player level but the requirement to get this card is 100,000 points per year. This translates to around $2-4 million in play per year, depending on what games you play.

As an example, a person playing $5 slots at a fairly high speed could meet this level with about 300 hours of play.

I don't think there are any public figures on how many 7-Star players Harrahs has but my guess would be only a few hundred.