I didn't think it had been sold, I think it is just leased to Collados (the same people who run the club house).
It is definitely no longer exclusive to owners - open to the public
It is right round the end of La Manga strip and the entry fee is €12 per person with towels and beach chairs costing extra.
Pool only open in the summer - though I think the restaurant is open for a slightly longer period
Website here - http://www.grupocollados.com/collados-beach/
Only in Spanish though and hasn't had an update on the news page since 2013 !!!!!