Maybe this forum is so successful because it does tend to focus on one manufacturer. For those with Canon equipment, it's a great way to learn because we can all speak the same language with something in common. If the forum were to be diluted with discussions of all kinds of other brands (and if you have Nikon, then you open the door to everything else, too, right?), then this forum would lose much of the value it has to most of the people here. Calling this forum close minded because it doesn't have sections for other brands is itself a close minded viewpoint. Be open minded enough to understand why this forum works so well.
There are plenty of other forums out there with areas for all types of different equipment, if that's what people want. There are Nikon-specific forums and many other photography forums available. If you want to talk Nikon, and feel the existing offerings out there aren't as good, then what's stopping you from establishing the next great Nikon forum?
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