The real Brandon

I own a 2007 es350. What mileage/km interval is recommended for replacing the plugs?

Many thanks.

Brandon

"[My] Lexus dealer [suggested] I change my oil once a year based on my 12,000 miles-per-year driving."

I've had a devil of a time trying to determine the proper oil-change interval for my 2007 es350. Aside from the once-per-year recommendation, am I to understand that 12,000 miles per year is the recommended interval? I realise this is an old post but I'm hoping somebody will supply me with a recommendation. 

Cheers!

Brandon