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1 install across multiple domains can be done via domain mapping - and I recommend you do that. The cctld domains will help you rank locally and having 1 wp installation requires much less maintenance. In addition, use a plugin like WPML to easily manage multiple languages and let it handle the SEO for you (by setting up proper sitemaps and hreflang tags)

Hi Stephan, Before you spend _too _long on this, I'd make sure it's the best use of your time - regular images do work on retina displays and so you may have higher priorities. In many ways (simplicity, maintainability, design) the best route is to use retina-ready images throughout your site and serve them up to non-retina users as well. This typically results in better images for all and doesn't have to impact filesize too much (see this article about compressing larger images). The downside is that for certain kinds of images, the larger image will still have a much larger filesize and this can be a major speed issue - especially for those on mobile connections. Unless you have evidence that one or other effect (fuzzy images on retina or slow loading) is causing you problems, I would personally take an "if it ain't broke" approach. The complexity of maintaining two sets of images is a step too far for most websites in my opinion and I would tend to stick with regular images up until the point where high resolution displays are significant among your users and plan to switch to high-resolution images for all at that point. I hope that helps.

Hi Stephan, I agree with Scott that this is possible but question how much more trouble it would be to run two installations for the two blogs? The canonical tag will take care of the duplicate content. I don't see much wrong with duplicating using this approach if the duplicated full article is better for users on the non-canonical site, or using the snippet + link approach if that's fine for usability / reader interest.

As long as the search engine can read all the text, I see no issues.  Modern designers put text in multiple tabs or partially hidden until expanded all the time these to create a better user experience.  It is generally only hidden from the user using css and is fully visible in the code.

Thank you everybody for the assistance. I really appreciate it. Along with your help and another resource I talked to, this is what I'm going to do. It's now clear that I better rely on breadcrumbs and a category link on these pages. So I'll keep it simple, use the category page and I'll add introductory content to that page. I'll try this for  two months, see how Google handles this and decide whether this works better or not. Thanks again, everyone!