I would say it is normal for a webmaster to look at other sites for ideas. Just make sure you dont copy all of their ideas. Or at least make some changes.
I feel that it is completely okay to look for inspiration and see how other successful websites do it. The key is not to simply copy-and-paste the information you see there. Find your own modified idea from examples shown, write it in your own style, to make it completely new. Visitors and members are not going to be interested in copy-and-paste information, especially if it's the kind of idea which have been used too many times.
I think it's OK for inspiration, but if you're just copying their content, then you're doing nothing to try and be unique and different from the board you're looking at. If you're just mimicking someone else, why would anyone bother to go to you when there's another board already doing it and much better.
You have to know what you're getting into. Checking other websites to get insight is a great resource. Do check other websites and pass as a member and ask yourself what is what you enjoy and what is what you think they are not doing okay or could do better.
Try to understand the bigger picture. Instead of taking the way they separated the layout, try to understand why it works or what were they looking for when they chose it.
This way instead of having scrambled specifics you will get a general notion and will make you feel with a better grasp of what you can apply to make your place work.