In old days (Befor they made it easyer to level) Vanilla Wow (1-60) was capable of leveling in just under 5 days played time with changes I belive that time is now just under 4 (This is with out RAF) so Its doable (RAD makes it easer BUT still can be done in short order but its really up to you.

I have seen people do 1-60 none Raf in under 5 days played time (I have seen RAF done in Over 5 days played time,

So as I said its really how organised and how much you want to put into leveling.