Request for references on multicommodity flow-cut results
I can recommend my recent paper http://arxiv.org/abs/1110.6832 on multicommodity flows and cuts in polymatroidal networks; we generalize several known results in standard graphs. Although we do not give a nice table summary we discuss many of the known cases. Some of the results that are not discussed in the paper but are of relevance are those for planar undirected graphs and some special cases. These include the result of
Satish Rao on $O(\sqrt{\log n})$ bound on flow-cut gap and tight bound of $2$ for series-parallel graphs by Chakrabarti-Jaffe-Lee-Vincent and some others. James Lee has several papers on flows and cuts on these graphs and any relatively recent one will discuss the existing literature.