I bought a 'Introduction to Photography' book for a young family member some months ago, alongside gifting them my K200D. It was a good book, with technical and composition info, and lots of good hands on guides to camera settings.
Although the book was careful to mention that there were other camera brands, and said that most modern DSLR's had essentially the same PASM controls and features nowadays, for consistency purposes, I guess, they only displayed either Canon or Nikon bodies, menus and controls in their illustrations. Perhaps this kind of material leads some people - even instructors - to sometimes assume that Canon and Nikon are the only game in town.
Originally posted by Brooke Meyer but I do end getting donations of legacy Pentax & Ricoh gear from folks with hair even grayer than mine
This is a very useful point. Older people know and remember Pentax, and often with much fondness. Younger people simply have no idea what a Pentax is. Over the last decade or two, Pentax marketing has really failed to connect the brand with the under 40's, it seems, let alone the under 25's.
A case in point: over the weekend I was shooting a car rally. Some older retirement age spectators recognised that I was shooting Pentax, were impressed by my K-3 and 70-200 rig, and started a conversation about how they had a Pentax camera years ago, and thought it was fabulous, but hadn't seen one in use for years.
However two younger pro shooters at the same event, with Nikon APS-C's, initially looked at me like I was from Mars, and totally couldn't figure out what the hell I was shooting with (I had the K-5 and K-3 out).