I'm a Linux user since around 1995, and a Gentoo user since around 2005.
I work commercially on larger scale web-connected systems these days but have done everything from embedded Linux to mobile applications. I see Gentoo as the spiritual successor of Slackware, a kind of manageable, BSD-oriented Linux distribution that isn't ashamed to show you the guts of the system. It lets you break things, but tries to stay out of your way.
One of the best things about Gentoo is the community, who are generally really well informed, friendly and available to answer niggling questions on IRC!