Robert De Niro got into a heated arguement with Jay-Z at Leonardo DiCaprio's birthday party in NYC.  Appearantly De Niro was unhappy about Jay-Z not returning his phone calls, after he called him six times about recording a theme song for the Tribeca Film Festival.  One source at the party said De Niro wouldn't calm down even when Beyonce came over; another source close to De Niro says it was a private conversation between the two and not a big deal.  I hope they weren't arguing over the title of "King of New York" - that belongs to Tim Tebow right?