Many product images including the standard images (useful for comparison) have been added to the Canon EF 24-70mm f/2.8 L II USM Lens Review page. Some direct comparisons are available on that page - including a comparison between the 28-70 L and the 24-70 L version 1.
Standard product images were also added to the Canon EF-S 18-135mm f/3.5-5.6 IS STM Lens Review page.