I've added a link to Lloyd Chambers' diglloyd website & blog, a really useful resource for equipment stuff. Things I like about his site: the objective outlook, his strong opinions providing a counter to most of the stuff out in www land. It is also one of the few places where you can get side-by-side info on Nikon vs Canon, with no bias. Whilst I'm not (never have been) a fan or user of Nikon I think it's good to see the other side once in a while.
The key reason I've linked, though, is due to his manner of looking at lenses. This has informed some of my approach to evaluating my own lenses and the work I've done on my on-going EF-S17-55 review.