I think Juventus have a better chance of beating them now than they would have had in the knock out rounds, purely because they don't have to play at the Camp Nou. It's still a massive stretch though, Barcelona have only lost a couple of finals in the past 10 years.
I am looking forward to the game more than other recent CL finals, either Messi wins the CL again or Buffon/Pirlo do. Personally I hope Buffon does - he really deserves it.