I've been using ACDSee (browsing, scanning and basic editing) and Corel Photopaint (more detailed editing) for a couple of years now.
Never really got into Photoshop; for a number of years I used a program called Micrografx for all editing tasks, but they were subsequently bought by Corel, and a number of the features ported into Photopaint. I like the fact that PP has a simple to use "stitch" function, for joining multiple images, or parts of a larger image together.
At the end of the day though, it's all about what gets the job done easiest I suppose