How many do you think are eligible for the club today? I would think it is far less than 5000 individuals, maybe closer to 500.. 
Let's revisit this during times of despair in the markets. 
So... more or less than 500 now? I would guess less. The distribution function continues as volatility rolls on.
300 to 500 is my guess.
There's 712 addresses with 2000 or more bitcoin currently. 549 of these have 2100 or more.
The majority of bitcoin users aren't storing all their coins on one address, but it's also safe to say that many of these addresses are owned by single individuals (Draper, Winkelvoss twins etc).
My random guess is about 400 different groups/individuals. As bitcoin begins to move towards $1000 again, there is going to be a massive psychological barrier for members of this club that have held that amount during prior bubbles. I think in the short term this group will grow smaller before it expands as members sell their coins off to large groups of individuals investing in bitcoin for the first time.
With every bubble people may be very willing to liquidate at least some amount of those coins in order to be 'safe' not to have lost the opportunity to at least keep some of that wealth.