Improved algorithm

While getting to grips with our new search algorithm we noted that, whatever we did certain eTextbooks appeared 'too' high on our results page. When I say 'too' high it's a reflection that eTextbooks might not be as evidence-based as other resources. Ok, they might be the best available evidence - but if they appear above 'better' evidence then the problems arise. So, to cut a long story short - we've built a fix and this will be tested, and dispatched, sometime next week.