Have to say it was the design and boredom/frustration with windows boxes and everything else. I started with the iPod (3G), i was frustrated and how hard it was to use my iRiver player. I got the iPod and was mesmerized by how simple its interface was, good looks and good sound to boot.
Then a while later, the Titanium PowerBooks caught my eye (backlit keyboard), they were just sooo gorgeous and different but the prices weren't (£3000+) which was kind of a turnoff. I didn't even know that Apple made them at the time i just wanted one but couldn't afford
THEN in selfridges store, i saw an half-eaten Apple logo lit up from the back of a laptop (i like things to light up) and got curious, went to play with it (a 12" PB). These things looked good/portable/quiet compared to the normal grey dell boxes. I tried the OS and aqua was a beauty too look at and things were just zippy. I was hooked
Soo i started saving, sold my Dell inspiron and bought a 12" PB as soon as they were updated to the 1.33GHz model and have never looked back since