/dev/random or urandom for encrypted swap

[Nomen Nescio]

I used the Ubuntu wiki's instructions to set up encrypted swap on my
computer, then I noticed whenever I booted it up, it would sit for a
while until I hit return a few times.

I think I figured out that the problem is /dev/random is "close to
empty" when the computer's just booted, so I changed the line in
/etc/crypttab to use /dev/urandom instead. That fixed it, so now it
keeps going through the boot-up stuff right away.

Has anyone else noticed this?

How insecure is it?

thanks