This sounds very interesting. If you've time could you outline what you've included in these posters in a little more detail - or send along the files so they can go online for all of us to share.
For the first time this year the History dept has been putting 'critical steps' to improving historical skills, based on the NC skill areas, into every KS3 student's books. These will be accompained by posters for every classroom which can be used by the teacher to direct the pupils to these areas.
Closest I get to this is putting student speak level descriptions in books / folders. Having attractive posters based on the different skills would be a great asset as they'd be more widely accepted and appreciated by a large minority of my students.