I have a warlock on the Silvermoon server. The first 18 levels were slow. Then I met up with 2 good levelling buddies from the UK and the remaining 48 levels were quite rapid. It took me from Jan 2006 to May 2006 to do the 60 levels.
I joined a raiding guild last month. The best bet is to choose a guild that lets you choose how often you raid. If you're compulsively addicted, then you raid every day. With me, I tend to do Onxyia on Mondays (takes about 1hr 30 min), Zul'Garrab on Saturdays (takes about 3 hrs, before I got out clubbing) and sometimes, Molten Core on Fridays (4 hrs).
Still, I go clubbing 1-2 per month and the pub 1-2 per week.
I must say that WOW is addicted for me not because of the raiding but for the penfriends / acquaintances that I have managed to get.