''Sex and the City" continues to be a convenient descriptive touchstone for critics. As in, ''This new show is 'Sex and the City' with lesbians," or ''That new show is 'Sex and the City' in Birkenstocks." That's because so many TV writers and producers still use the classic HBO series as a model around which to design their potential Nielsen hits.
Yeah, they clone it.
Which brings us to ''Emily's Reasons Why Not," the new ABC sitcom starring Heather Graham. It's not half bad, but then it's not even a quarter original. The romantic comedy, which premieres tonight at 9 on WCVB (Channel 5), is such an obvious rip-off of ''Sex and the City" that you'll find yourself drawing comparisons for the whole half-hour. See Graham doing her best Sarah Jessica Parker as a fashion-conscious New York editor. Hear her plaintive voice-over narration; meet her loyal best girlfriends, including a gay man; and, of course, get a load of her Mr. Big, an emotionally unavailable writer played by Mark Valley.