I will never own an automatic if I can help it. That 10 speed is cool and all, but I can't imagine it being anywhere near as fun as a stick. No thanks.
edit - The auto is more expensive. In 2011, the 2SS auto had the gas tax, but the manual did not, if that's anything to go by. I really doubt any ZL1 will avoid it though, so I'd rather go for the more fun option. Also, thieves are dumb as **** and can't drive a stick.