After being a rock uber-god for years, how much more money do you need? For Steven Tyler, that answer rings in at about $2 million, which is what he's getting for optioning his memoirs to HarperCollins. That should keep the big-lipped singer happy for awhile unless, wuh-oh, he takes a look at how much Keith Richards got for his story, just last year. Hint: It's a lot more.

The Rolling Stones' guitarist made $7 million for his book in 2007.

Eric Clapton's biography Clapton, which came out shortly after, made "Doubleday Publishing Group’s bestselling titles of 2007."

Then there's the compilation The Heroin Diaries from Motley Crüe's Nikki Sixx, which came out earlier this year and made it up to No. 7 The New York Times Bestseller List. And Sixx's memoirs had the benefit of not having a ghostwriter and giving the proceeds to charity.

So how will the Tyler memoir do?

Probably somewhere between Tommy Lee's Tommyland and the Dave Navarro autobiography.

More importantly, will Tyler's tome be worth its buying price, for readers or publisher? Probably not. But rock stars are used to getting paid extraordinary sums for behaving badly.