My mom did CDs (prefolds + "rubber pants") on me and my brother, same with my aunt with my 4 cousins. So, to me it was a normal thing, even though I don't specifically remember it. And sposies were normal to me, too, b/c I babysat a lot when I was a teen. Anyways, once we came to where we were thinking of having kids, I figured I probably would use CDs (prefolds + "rubber pants) but I figured I'd use sposies for the first few months - just until I got a grip on the "baby thing", THEN I would be able to do more work and use CDs.
When dd was about 2 months old, some people were having a discussion on a parenting message board that I go to. They were discussing their favorite CDs. That was when I realized that there were options other than prefolds... and then I felt soooooooooo confused by all the options. I remembered a friend a few years back had used CDs with her baby, so I called her and asked what she used (Motherease Sandys). I researched more and was just amazed at all the options.
Well, with all the fun options out there, I decided against prefolds and "rubber pants"! From all of my research I decided that pockets would probably float my boat. So, I bought a FuzziBunz from eBay. I shoved one of my burp cloths (a Gerber "cloth diaper" from BRU), put it on dd, and decided I liked the set-up! Of course, she peed right through that burp cloth, so I decided I would buy Joey-Bunz. (I hadn't wanted to buy one prior to trying the pocket, just in case I didn't like the system.) Then I started my buying spree on eBay - I bought a stash worth of FBs and JBs!
And it's gone from there. I still mainly buy all used (why not? - they're still in great shape, and they work just as great!), but I have ventured out into other dipes (Happy Heiny's, Wonderoos, Daisy Doodles, some fitteds and wool/fleece covers for rashy times, etc.), and I'm venturing into new territory with our DS due in Oct/Nov (Kissaluvs 0s + covers, and then other brands of pockets that I've never tried).
My main reason for cloth diapering? It's fun! When people ask me why I do it, that's what I tell them - it's fun! I enjoy it.
ETA: When we've done sposies on road trips, I've ALWAYS looked forward to going back to cloth. When I didn't know better (before I started CDing), the gels didn't bother me. But now that I know better, the gels on dd's bottom while doing sposies REALLY REALLY REALLY bothers me. Plus, it's a pain to be running to the store and buying dipes all the time!