Years of Photoshop skills wasted. Or perhaps just a precursor to the destination I have found with the Gimp. The interface is different but the workflow is nice. In Photoshop I was an intermediate user with the Gimp I finding that I'm becoming an expert faster. Maybe I'm just too excited.
As a novice user my favorite feature was the detaching menus, so you can leave the filters menu and others on the screen for convenient clicking. This is great for new users who just need to get things done. Another love is the right mouse button menu. It lists all of the menu options from the top of the screen. Much quicker if you have been working in a tiny area of the screen for some time as artists often do.
The downfall with the Gimp is the text rendering. It doesn't seem to support letter spacing at all, the only movement allowed is line spacing. Scribus does a better job of doing this for print layouts but for web work I almost want to stay in the Gimp as much as possible. Designing website comps outside of a graphics suite would shock and amaze the people in my office. We only get Photoshop files. This file dependency also causes a problem as the newer versions of Photoshop don't layer right. Always get a Tiff to verify you're looking at the same thing as your clients.
Most people don't use Photoshop that much but they still need some basic graphics editing. If this sounds like you the Gimp will do your task. For the super math kids in the crowd, you probably already know how fun this software suite is. Have fun everybody.