I say give Arena a chance through this WC cycle. He's been successful at every level he's ever worked. Several college championships with UVA, with a program that was non-existent when he started. 5 MLS Cups, with 2 different teams. The USA run at the 2002 World Cup was pretty special.
Klinsmann did some good things, which will continue to reap rewards in terms of the talent pool. He deserves credit for that. It's just that, as a coach, he ran his course.
Did you watch that Costa Rica game. I've watched a ton of USMNT games over the years. That was the worst one. I saw players giving up. The USMNT has always been about heart, but they quit on their coach in this game.
I'm excited about many of the young players right now. I think Arena is the right guy to not screw this up. He's a big proponent of not over-complicating things. I think he will get the best out of the players and I think players will be reinvigorated.
EDIT: Think of it like this. Bruce Arena is kind of like the USMNT's Wade Phillips.