To all of those who were QQing about Horde getting a Scorpion while Alliance gets a lion for the guild mount I present you:
Courtesy of The Wowhead Blog's Latest Post.
I think Blizzard hit the epic-level pretty accurately here. The white space is presumed where your guild crest will go.
As many have said, you should really go check out the wowhead model viewer. Looks much better than my pics.