Aha, it wasn't probably ever working exactly as written in the "Steps to Reproduce:"

With    rhel-guest-image-6-6.5-20140121.0-1, which has 

  console=ttyS0,115200n8 console=tty0 

on the cmdline, the command

  [root@bar cloud-user]# echo console > /dev/console

doesn't output the "console" to the ttyS0, but only to the tty0 and the boot messages are with color codes:

  Setting hostname bar.beerdrop:  [60G[[0;32m  OK  [0;39m]


However, if there is

  console=tty0 console=ttyS0,115200n8 

the output then goes to the ttyS0, but not to tty0.

  Setting hostname foo.beerdrop:  [  OK  ]


So, I would rather preferred the messages without the color codes as it makes the messages more readable in the log, though we don't get the eye candiness on the tty0. So if this has no other implications, I would recommend to change the command line to  console=tty0 console=ttyS0,115200n8.

Version:
rhel-guest-image-6.6-20140910.0.x86_64.qcow2

Steps:
1. #echo asdfasfasdf >/dev/ttyS0
asdfasfasdf
2. # echo adsfasfasdf >/dev/console
adsfasfasdf
we can see both ttyS0 and console are output to console.

Verified as above.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2014-1697.html