I have been experimenting with the tiling of large georeferenced images so that only the sections being viewed need to be downloaded. Again Google Earth allows the most options for display of layers, but it is not often installed on public computers. I have not taken the time to learn a lot about the mashup options for Google Maps and Bing, but my initial experience has been that they are more complicated and not as full featured. I look forward to hearing others experiences.

My philosphy is to always maintain the original tiff scans, so that I can always reformat any images for newer technology.

I recently read somewhere about the DjVu plug-in and it’s marketing/branding strategy. The message was that they do not really have one, which ultimately hurts sites that use DjVu. Unlike, say, Adobe Acrobat or Flash, you cannot count on users having it installed (this is also true for Adobe plug-ins, though to a lesser extent I imagine). Have you had this problem at all with Rails & Trails? Or do you see any barriers to using Google Earth as a vehicle for GeoReferenced maps? Are you aware of any web/browser standards (current or in development) that apply to this kind of work? Does openstreetmap.org have any use here or is Google/Yahoo/MS really that much more developed? I tend to embrace open source alternatives whenever I can, but with mapping, I’m not that knowledgeable, so I’m not sure what’s out there. In any case, I find your site to be extremely useful and know that faculty/staff here at CSU often recommend it to students for research, so I’ll be curious to hear more.