How well does buildr subsume rake?

[Olivier Lefevre]

While we are talking I have one more question: how much rake
do you need to know in order to make good use of buildr? I have
to ask because the rake docs: http://docs.rubyrake.org/ are just
the kind of stuff that would make anyone with common sense
run for the hills. To call them minimal is kind; they are probably 
out of date, too.

Thanks,

-- O.L.