The in thing?
The "in" thing is a computer with an operating system. You'll find very quickly that there isn't a linux/unix distro that is "in". Everyone has there favorite and everyone has different tastes.
However, if you're wanting to be a master of linux/unix, you'll become familiar with most of them. Don't take too big of a bite too early though, stick with one distro for now. If your first download was red hat, use it until you know it.
