username: cirros
password: cubswin:)
that's "cubswin" followed by a "colon" and "close-paren" (smily face)
e.g.
clayg@devstack:~$ ssh cirros@10.0.0.2 Warning: Permanently added '10.0.0.2' (RSA) to the list of known hosts. cirros@10.0.0.2's password: cubswin:)
Just as an aside, the dropbear ssh server on the cirros image allows root login by default, but the root user's password on the image is basically disabled:
root:!$1$LJwQnqlv$DK6oKqcTq9Rf2ClC.kMa3/:10933:0:99999:7::: cirros:$1$LJwQnqlv$DK6oKqcTq9Rf2ClC.kMa3/:10933:0:99999:7:::
... that leading "!" in the encrypted password field for "root" in /etc/shadow makes all the difference. If you remove it, you can see it's the same hash as the cirros user and the "cubswin:)" password works for root too.
If you're just having trouble getting into ssh/port 22, a bit of security groups should square you away:
nova secgroup-add-rule default tcp 22 22 0.0.0.0/0