Santa Monica-based eHarmony, the online relationship matching service, said late Tuesday that CEO Greg Waldorf has stepped down as CEO and board member of the firm. eHarmony said that Waldorf has served for more than 11 total years for the company, five years as CEO. Waldorf also was the founding investor in eHarmony. eHarmony said that President and COO Greg Steiner takes over Waldorf's responsibilities and will lead the firm, which the company's board conducts a CEO search. In a steatement. Neither eHarmony nor Waldorf said why he decided to step down, however, eHarmony praised Waldorf's tenure at the firm and hailed the milestones achieved under his direction.