Daniel Libeskind has been well-known in architectural circles since his first major building went up in Berlin more than a decade ago. But since being selected as the architect who will replace the World Trade Center, Libeskind has had to learn to live with a whole new level of celebrity. People stop him on the street, offer their unsolicited opinions on his design, and generally treat him with the same level of awe the Big Apple affords to such local heroes as Derek Jeter or Rudy Giuliani. Celebrity has its downside, of course, but for the moment, Libeskind seems to reaping all of its rewards.