When I was pregnant with my DS three years ago, I chose a somewhat jungle-themed set of bedding and decor. It was called "Mommy and Me" and had mama and baby elephants, bears, alligators, giraffes, etc. But it wasn't really in bright colors, more tans, browns, reds and greens, gender neutral.
But I would say that the bright colors and jungle animals are definitely in. Fisher Price has a new line of highchairs, bouncers and the like with a focus on jungle animals. If you ever want to know what's "big" in children's decor, just take a stroll through Toys R Us and you'll see.