Just a passing thought, at http://files.pharo.org/books/
it might be nice for the top descriptive text to indicate a reading order. ��
Something like...

�� �� Newcomers should start with Pharo By Example, then proceed��to: ��
�� �� - Spec UI Framework for desktop applications,��
�� �� - Enterprise Pharo for web development,��
�� �� - Agile Visualization for data processing.
�� �� Deep Into Pharo and Numerical Methods are broadly applicable to all three domains.

cheers -ben