The (hope­fully many) green blocks at the right side of the menue are indic­at­ors for when the pages, files or links behind the menu items were last mod­i­fied. This may help you find­ing the most inter­est­ing and cur­rent inform­a­tion on this web­site. It is only a little gim­mick, but … well it may be use­ful. It is at least for me. ;)
There are by the way sev­eral other func­tion­al­ity enhance­ments: menu items may now be col­lapsed for a bet­ter over­view. The per­sonal pref­er­ences are stored for the cur­rent ses­sion only, so when the browser is closed, the con­fig­ur­a­tion is lost. Nice and sense­less, isn’t it :).