"Rock music has become like soap opera," says John Flansburgh. "It has every element of real life except humor." Flansburgh, 28, and John Linnell, 29, are They Might Be Giants, a dowtown New York duet. Their new album, "Lincoln," has a romantic song about a Vietnamese woman, "Ana Ng," that just bumped U2's "Desire" from the No. 1 spot on college radio. TMBG's hard-core fans track the group on Dial-A-Song, its phone-answering machine. The two-man band is very funny, but also serious, as in the pop satiric "Youth Culture Killed My Dog." TMBG wears its new success lightly. "We're misunderstood because we have a bit of levity," says Flansburgh. "Our songs say something." TMBG has been a brand-new band for six years. "When you reach a new plateau every couple of months," says Linnell, "people keep saying, 'Look at my discovery.' "