If you currently own an I-pod you'll probably not like it, this is nothing to do with the player but more to do with I-tunes which tends to spoon feed its customers. If your reasonably PC savvy you'll probably love it like me. The Creative software isn't bad (Creative Media 5) + you'll need a couple of freeware utilities Like Handbrake (DVD ripping) and I use mp3tagtool to sort out the tags and add album art.
Build quality, features etc the Zen is comparable with the iPod but as two added benefits; first it's cheaper for the same abilities and second it does not superglue you to iTunes and Apple's revenue stream. I wouldn't be seen dead using anything from Apple but I do like the features, the Zen fits the bill very nicely. The fact that most people buy iPods means that the Zen, along with every other mp3 player is more exclusive by default. Like a Ferrari is always Red, iPods are always white and therefor distinctive. Yes you can buy them in different colors but these devices tend to be bought to show off like trophies to gain kudos points. To me, seeing someone with white ear-buds says "I have an iPod, mug me".
Do you pay a premium to go with the crowd or save some money and blaze your own path with a better (in my opinion at least) device? It is Windows centric though so your user experience will be different on either Linux or OSX as you'll have to use a third party application to interact with it. Gnomad2 for Linux is what I use. Apple like to ensure that your iTunes / iPod experience is flawless while ensuring that every other mp3 player in competition is intentionally screwed over.