USA TODAY -- Feb 14 -- The industry has grown so fast that Hitwise foresees a shakeout. Says Mark Brooks, who runs Online Personals Watch, "I think we're moving into the first stages of maturity." So companies are trying, like the most desperate bachelor in the bar, to stand out. Those who market love on the Internet are increasingly wooing customers by giving personality and compatibility tests. For the strongest players, the cyberspace dating game remains lucrative. In December, for instance, eHarmony attracted $110 million from two venture-capital firms. "What kind of metrics must eHarmony have shown the VCs to get $110 million?" asks Brooks. JupiterResearch says online-dating revenue hit $473 million in 2004, up from $396 million in 2003. <On background checks>..."That's a solution looking for a problem," complains Jim Safka, the new CEO of rival Match.com. But some competitors grudgingly admire the marketing strategy. "It was brilliant," says Nelson Rodriguez, CEO of LoveAccess.com. "You try to legislate into law your business model." True's CEO Herb Vest warns: "If a person is married or a criminal, they best go somewhere else." True says it intends to prosecute married people who masquerade as singles. "We don't think of ourselves as an online-dating service," says Greg Forgatch, CEO of eHarmony. "We're all about helping people get married and get married well." Yahoo has launched Personals Premier, a $35-a-month service with advanced searching and matchmaking and a personality test. IMatchup.com has unveiled a handwriting-analysis feature. Niche sites proliferate. "I'm not promoting Cupid.com anymore; I'm pitching DesMoines.Cupid.com," says Cupid.com CEO Eric Straus.