> If 'fanboys' is considered an offensive slur (as it appears to be) then I'm personally happy to use the term 'Apple fans' but they are essentially referring to the phenomena/grouping.

Please do. 'fanboys' certainly is not a distinct term that is useful to describe a cluster of people, as you say, at least not any more.

Aside: Harry McCracken recently wrote a (rather long) essay on the origin and evolution of the word 'fanboy': http://technologizer.com/2010/05/17/fanboy/