fungus:
That's correct, but pull-down resistors are a bad idea - you should have as few wires going to the 5V supply as possible in your circuit. Bad things are far less likely to happen if you do that
Cargo-cult circuit design - the electrons simply don't care whether you use pull-down
or pull-up, there's no reason there.
Where it does matter is when using remotely mounted switches, since you have to
run +5 as well as signals and ground (you want ground for the cable shield).
With pull-ups you can omit the +5v wire and connect the switches to ground instead.
You also have the advantage that if the cable gets crushed or cut the supply won't get
shorted out.
However if the circuit's all on one board these issues aren't relevant and the
choice between pull-up or pull-down is arbitrary. The availability of on-chip
pull-ups means pull-up is convenient, but there are no "bad things" that happen
if you use pull-downs.