Itís no secret that Arthur Cohen is wasabi-hot. Never mind the museum officials, er, potential new clients, hanging around him all weekend. Cohen's Saturday session in the Sheraton ballroom was packed. And we mean find-a-spot-on-the-rug packed. Cohen's panel talked about the ďYoCos,Ē the young cosmopolitans that every museum is desperate to attract to broaden membership and start nurturing the next generation of art philanthropists. First, Cohen and Steve Rogenstein, a seriously-mustached senior strategist for Cohenís firm, LaPlaca Cohen, showed an acid-drenched clip meant to illustrate the diversity of these Yocos. As far we could tell, they have tattoos and thick glasses and don't seem to eat a lot. And one Yoco definitely looked like the dead guy from Milli Vanilli. The serious point, though, is that there are 17 million of these YoCos running around - smart, active, tech-savvy consumers - and as Rogenstein said, ďtheyíre willing to spend their money."