The one thing I don’t like about the Play website example is when you’re digging down into the content, they don’t make it very easy to browse through the books/music/etc. There is a left-hand navigation in some of the sections, but when you get to the page for an actual item, it would be nice to make it easy for you to get back there.

In contrast, take a look at this random page from Barnes and Noble’s website. Not only do they have an effective main navigation where the section you’re in stays highlighted, they also use breadcrumbs to help you get back to the higher levels that you came from. I think in combination with everything else on their website, this works well.

I think the question of when to use it depends on the website. For some of the smaller websites that I’ve constructed, where the hierarchy only goes to a maximum of three levels deep, there’s not really a need. But for some of the more complex sites I’ve worked on (and that are out there in general), I think it makes more sense to incorporate them.

I’m not the biggest fan of the breadcrumb trail personally, and will only implement it in the case that a client is insistent on its inclusion (usually when there’s a large amount of available menu options or sub-categories).

I believe that if you can show the user where they are, using the menus available on the screen at that particular time, then that is a better ‘design solution’. The best example I can think of for this (off the top of my head) is the current Play website.

Digg used to also do this, but I’m not such a big fan of their new drop-down navigation, as it no longer displays the sub-category you’re in (perhaps they should add a breadcrumb trail?).