Gentoo, one of the most powerful Linux distributions around, has a reputation for being extremely hard to install and use. Sabayon makes it easy, coming with graphics by default and the Anaconda installer. Sabayon retains the functionality of Gentoo and portage, but also introduces some new features, the most noticeable being the Entropy package manager. Note that all the below information pertains to Sabayon 7
Entropy is the binary package manager for Sabayon. It installs binary packages that the sabayon build server compiles from the portage tree, much like yum or apt could. Gentoo is a source-only distro, so this is a vast improvement if you have little knowledge of compiling packages. To invoke Entropy use the command equo. Equo has a beautiful command lines displays which are fully colorized for quick interpretation. Equo automatically handles dependencies, so installing a package is as easy as invoking equo.
Sulfur is the graphical interface to equo. It is not install by default, so you must use equo install sulfur as root to install it first. Then, you can use the sulfur command to start the package manager or use the "Entropy Store" link on your desktop. I would highly recommend the advanced mode that sulfur comes with as the non-advanced is a bit simplistic.
Remember, Sabayon is based on Gentoo, so you can still use portage. Just use the emerge command. Be warned, however, as mixing Entropy and Portage can severely damage your system. Pick one to carry out activities.
There is one thing to note, however, and that is that equo update updates the repositories, not the system. To update the system use equo upgrade. Updating the system will scan configuration files and replace them when it does and you allow it, so upgrading may fix breakage.
Sabayon comes with a range of desktop environments (you can choose which .iso to download), but they are all installable via Entropy. Gnome 3 is the desktop environment that I chose, and I noticed something right away; sane defaults!
Gnome 3 comes with an icon-less desktop and only a close button, but in Sabayon it comes configured the way a normal person would use their windows. Gnome-tweak-tool is also installed by default, so if you prefer to use GNOME a different way you are free to. I have also tried e17 and rather enjoyed it, but a graphics problem disallowed me to continue using it. Whether or not it was a problem with the e17 package or my computer I never found out.
This is one of the most noticeable things in Sabayon. The GRUB splash screen is both readable and pretty, as well as the boot. The boot process has probably the best display out of any Linux distribution I have used thus far. It shows a progress bar, text readout, and explains how to enter verbose mode. Even in verbose mode, the output is contained within the splash.
The terminal is even prettified. The default color scheme in the terminal has a great default color scheme: black background, green prompt, white text.
Stance on Freedom
Sabayon is not as freedom-heavy as other distros, but instead includes nonfree software from the get-go and has the nonfree repositories enabled by default. This means there is a great option of having driver support right out of the box, and if not, having it easily installable.
You may have heard of The Arch Way, the arch linux philosophy on computing. Their ideal operating system is a bare-bones system where the user determines how it will be structured. Sabayon is exactly the opposite. Sabayon's goal is to create a distribution that includes all of the software you will need in their default installation. Personally, I loved the software that was installed (Chromium, GIMP, Libreoffice) but others feel that it adds unnecessary "bloat" to the system. On modern computers, a few extra hundred megabytes of information isn't too bad of a thing; and if it is, you can uninstall it with Equo.
Sabayon has quickly becoming my primary operating system. I choose Sabayon because package availability is great, it is based on Gentoo and has portage capabilities, the aesthetics are great, and the original installation will be enough for most users in terms of preincluded software. In all of my previous distributions I have had to put up with some minor error, and I usually end up breaking everything trying to fix it. In Sabayon, I have come across a few errors, but nothing that an update won't fix. Sabayon is also a bleeding edge, rolling distro, so I may never have to reinstall it. I would highly recommend it to a distro-hopper or someone looking to try something different and useful.
My Sabayon Linux (names crossed out)