It's no joke. The Nets are serious contenders to win the Eastern Conference with Kyrie Irving and Kevin Durant each healthy and an excellent collection of talented role players. 
Brooklyn looked good in preseason going 2-0 beating the Celtics and Wizards by a combined average of 14 1/2 points. 
Golden State isn't at Brooklyn's level. Yes, Stephen Curry is back. That's enough to elevate the Warriors into a playoff contender. But that's it. Klay Thompson is out long-term and Draymond Green isn't expected to play in this game due to a foot injury. The Nets have much the stronger bench.